Apple's new laptop, the MacBook Air, may not be the true ultraportable that many had hoped for, but it still easily breaks new ground for small laptops. Mimicking the 13-inch silhouette of the current MacBook line, it's only 0.76 inch thick at its thickest part, and Apple calls it the "world's thinnest notebook." Some nitpickers say an obscure Mitsubishi laptop from 1998 was a hair thinner, but two of the smallest current ultraportable laptops, the 11-inch Sony VAIO TZ150 and the 12-inch Toshiba Portege R500, are both slightly thicker, and neither tapers to 4 millimetres as the Air does along its front edge.

As we've come to expect from Apple, the design and engineering that went into the MacBook Air is extraordinary, but it's certainly a much more specialised product than the standard 13-inch MacBook and won't be as universally useful as that popular system. The biggest compromises, which have been well-documented, come in its connectivity: The MacBook Air finds room for only one USB port and doesn't include a built-in optical drive, FireWire, Ethernet, or mobile broadband. And like with its other laptops, Apple refuses to outfit the Air with a media-card reader or an expansion card slot. Off-setting its sparse connectivity are genuinely useful new features including new touchpad gesture controls and the ability to wirelessly "borrow" another system's optical drive.

Choosing the Air over the cheaper, faster standard 13-inch MacBook, or the comparably priced MacBook Pro, will depend on your needs. Travellers who want minimum weight but maximum screen real estate, and who live their lives via Wi-Fi hot spots with little need for wired connectivity, will find the AU$2,499 starting price a reasonable investment for owning one of the world's premier bits of high-tech eye candy. And while the MacBook Air's specs are inferior to those found on the cheaper MacBook, they compare more favorably when you look at other ultraportables, where a price premium is always exacted. For instance, both the Sony VAIO TZ150 and Toshiba Portege R500 cost hundreds more than the MacBook Air and feature slower CPUs and half the RAM as the Air.

Although it shares a desktop footprint with the standard black and white MacBooks, the first thing you notice about the Air is its aluminium chassis -- similar to the one found on the MacBook Pro, and much more fingerprint resistant than the standard MacBooks. Picking it up, the MacBook Air feels a little heavier than you'd expect from looking at it, even though it's only 1.4 kilograms. At the same time, it feels very sturdy and solid, thanks in part to the aluminium construction, and we'd have no qualms about carting it around with us all day. By way of comparison, the VAIO TZ150 features an 11.1-inch screen and weighs only 136 grams lighter than the Air, and the Portege R500 is 272 grams lighter than the Air with a 12.1-inch screen.

The MacBook Air includes an iSight camera and mic, and an LED backlit display that works with an ambient light sensor to adjust the screen brightness in response to the light in the room. The keyboard -- the same full-size version found in other MacBooks -- has backlit keys that are also controlled by the ambient light sensor, although we really had to adjust the room lighting a good deal to see any difference.

The revamped touchpad is large, measuring nearly 127 millimetres diagonally, and it works with new multitouch gestures. Other MacBooks let you do things like use two fingers to scroll through documents -- this one lets you use three fingers to go forward and back in your Web browser history, and use your thumb and forefinger to zoom in and out of documents and photos -- much like on the iPhone. The three-finger forward/back gesture was immediately useful, and we're already missing it when using another laptop. Apple tells us these new gestures won't be available on older MacBooks as a firmware upgrade, as the hardware behind the new touchpad is different.

Another noteworthy new feature is the remote disc function. Since the Air lacks an optical drive, you can instead remotely see the optical drives of other systems, PC or Mac, as long as they're on the same network. The setup was a little cumbersome for the "host" PC -- requiring us to insert the OS X disc that came with the Air, run a small setup program, and then find and turn on "CD and DVD sharing" in the Windows control panel (the documentation could have been a little clearer on what you need to do to on the Windows side). Once we set it up, however, it worked like a charm. You won't be able to stream DVD movies or music CDs via remote disc, but it's fine for getting files and installing apps. A matching external USB DVD burner is available from Apple for AU$139, but any USB DVD drive should work.

The display offers the same 1,280x800 native resolution as the standard 13-inch MacBook, but the Air's LED backlit screen means its lid is thinner with an image that was somewhat brighter, at least with both systems set to max brightness.

The real key to finding out whether the MacBook Air is right for you lies in its stripped-down set of ports and connections. Those who regularly use more than one USB device, or need FireWire, an SD card slot, or an Express card slot will find the single USB jack too limiting. Likewise, we often say the telephone modem jacks and S-Video outputs on most laptops are a waste of space, but the MacBook Air goes even further, removing the Ethernet jack (a USB-to-Ethernet adaptor will run you AU$39) and offloading video output to a pair of included dongles (one VGA, one DVI).

If you live on Wi-Fi hot spots, use Bluetooth for your external mouse, and only need a USB port to occasionally sync and charge your iPod or iPhone, these limitations may not be a deal-breaker for you. While most hardware vendors offer a choice of mobile broadband options, Apple continues to offer none, which is disappointing for a system so clearly meant for life away from home and office. Without an Express card slot, your only option would be a USB mobile broadband modem, but with the sole USB jack under a tiny flap on the right side of the system with limited clearance, you may need a small USB extension cable to get a bulky USB mobile broadband modem connected (similar to the problems people had with the iPhone's recessed headphone jack).

While the 80GB hard drive included in the base AU$2,499 model may be smaller than you're used to, the only other option is a 64GB solid state hard drive. With no moving parts, and advantages in heat, power consumption, and reliability, SSD hard drives are certainly the way of the future. The future may have to wait a few years for prices to come down, however; swapping the 80GB platter drive for the 64GB SSD drive is a whopping AU$1,409 upgrade. The only other internal hardware option is a CPU uptick, from 1.6GHz to 1.8GHz for AU$430. With the upgraded CPU and SSD drive, the AU$2,499 MacBook Air suddenly becomes a $4,338 laptop.

We are pleased to see that the MacBook Air comes standard with 2GB of RAM, but with a processor that runs at a much slower clockspeed than the standard MacBook (2.0GHz or 2.2GHz), plus a 4,200rpm 1.8-inch hard drive (as opposed to the standard 5,400rpm), it's not surprising that the MacBook Air is not as fast a performer as some of the MacBooks past.

As we often point out though, any modern dual-core CPU is going to be more than adequate for Web surfing, multimedia playback, and productivity tasks, and we were able to surf the Web, play videos, and work on a document at the same time with absolutely no slowdown or stuttering. We're currently conducting additional benchmark tests and will update this review with new results as they're available.

One of the biggest drawbacks of the MacBook Air is the lack of a replaceable battery. While most laptops will be obsolete before their batteries wear out, we are sensitive to the desire to occasionally carry an extra battery for extended field use. We're still conducting our standard DVD battery drain test on the system, and will report those scores shortly, but in anecdotal testing, the Air lasted for nearly 4 hours of mixed use, including video playback, software installation, Web surfing, and productivity tasks. That's reasonably close to Apple's 5-hour claims, but may not be enough for a full day of off-site use.

We're still not fans of Apple's nearly obligatory extended warranty upsell (so much so that we've simply copied this complaint from our last MacBook review). The default warranty for the MacBook is one year of coverage for parts and labour, but toll-free telephone support is limited to a mere 90 days -- well short of what you'd typically find on the PC side -- unless you purchase the AU$419 AppleCare Protection Plan, which extends phone support and repair coverage to three years.

System configurations:

Apple MacBook Air - 1.6GHz
OS X 10.5.1 Leopard; Intel Core 2 Duo 1.6GHz; 2,048MB DDR2 SDRAM 667MHz; 144MB Intel GMA X3100; 80GB Samsung 4,200rpm

Sony Vaio TZ150
Windows Vista Business Edition; 1.06GHz Intel Core 2 Duo Ultra Low Voltage U7500; 1024MB DDR2 SDRAM 533MHz; 64MB Mobile Intel 945GM Express; 100GB Toshiba 4,200rpm

Toshiba Portege R500
Windows Vista Business Edition; 1.2GHz Intel Core 2 Duo Ultra Low Voltage U7600; 1024MB DDR2 SDRAM 533MHz; 128MB Mobile Intel 945GM Express; 120GB Toshiba 5,400rpm

Apple MacBook Core 2 Duo - 2.2GHz / 13.3 inch
OS X 10.5.1 Leopard; Intel Core 2 Duo 2.2GHz; 2,048MB DDR2 SDRAM 667MHz; 144MB Intel GMA X3100; 160GB Fujitsu 5,400rpm