Notebook computers are hot - both in recent sales numbers and on your lap.  In fact, manufacturers have stopped calling them “laptops” because actual lap/thigh use can be downright uncomfortable, due to the heat generated by the current generation of dual-core processors.

High-end professional notebooks come close to equaling the performance and capabilities of consumer desktops, but the compact size and power consumption requirements of notebooks require feature compromises.  The smaller the notebook, the greater the compromises.

Earlier this month Apple announced the “MacBook Air”, which they bill as “the world’s thinnest notebook” (we’ll call it the “MBA” for short).  The “Air” moniker refers to two of the MBA’s signature features: weight (get it - lighter than air) and wireless (as in through the air, without wires).

Let’s look at the MBA’s “tale of the tape”.  It’s length and width measurements (13 inches by 9 inches) are the same as Apple’s popular MacBook.  However, the MBA is only three-quarters of an inch thick at its thickest point (the center rear by the hinge), and only .16 inch at the thinnest (the front edge).  That’s thin.  So thin that you could slide it under a door, or carry it around in a manila folder.  And it’s light.  Three pounds.  A full two pounds lighter than the MacBook.  The case is polished aluminum (like the MacBook Pro), and the MBA sports a full-size, backlit keyboard.

The MBA’s 13.3-inch diagonal display is backlit by LED (light-emitting diode), so it’s extremely bright, instant-on, energy-saving, and environmentally-friendly.  There’s a built-in iSight camera at the top of the display for video chat.

The MBA’s trackpad is capable of multi-finger, multi-touch “gestures”, similar to the iPhone.  For example, you can “swipe” through web pages or photo slideshows and expand/contract font sizes on web pages by pinching, to name a few.  Three I/O ports are found behind a flip-down door on the side: headphone jack, USB2, and a new micro-DVI port capable of running an external display or video projector.

The MBA sports a 1.6GHz or 1.8GHz Intel Core 2 Duo processor (custom-built for the MBA), 2GB of non-expandable RAM, and a 4200 RPM 80GB hard drive (the same type hard drive used in iPods).  You can also order an MBA with a 64GB solid-state drive, for a cool $1000 premium.  Fast 802.11n and Bluetooth wireless connectivity is built-in as well.  Apple claims five-hour life for the non-removable battery.

As with all Macs, the MBA comes loaded with Mac OS X “Leopard” and the iLife suite of digital lifestyle applications.  The price?  $1799 for starters, $3100 for the solid-state hard drive model.

Where does the MBA compromise to maintain it’s “girlish figure”. There’s no Ethernet port (a first for an Apple notebook since, well, forever).  You can buy an Ethernet adapter that plugs into the USB2 port for $29.  There’s also no FireWire port, although a third-party USB adapter won’t be long in coming.  And, there’s no internal optical drive.  You can, however, buy an external CD/DVD-burning SuperDrive for $99 (it plugs into and is powered by the USB2 port).

So, the obvious question is, if you don’t spring for the external SuperDrive, how do you install DVD-based software, like Microsoft Office 2008?  Well, Apple has included Remote Disk software that you can install on another network-connected Mac or PC that allows the MBA to “take over” the other computer’s CD/DVD drive and use it for installations (but not for watching DVDs or listening to music).

Do the feature compromises on the MBA outweigh its light weight and svelte good looks?  See the column next door for my take.