The main theme of the Consumer Electronics Show this year, in case you’ve been hiding under a rock this week, is the ultrabook. These lightweight laptops are chasing after the MacBook Air, trying to undercut Apple’s $1,000 price tag and add their own flair to the lineup of super-slim devices. Intel, the company behind the chips that make the devices “ultra,” has been pushing this newly named genre hard, announcing in its Monday keynote that at least 75 models are on their way.

There are three main distinguishing features of an ultrabook. First, they’re light and thin — really thin. Acer’s Aspire S5 Ultrabook is just .6 inches thick at its widest point, and the HP Envy Spectre 14 is .8 inches thick. Ultrabook makers favor solid-state hard drives that start up quickly and don’t add nearly as much weight to a device as a traditional laptop. Design is the key factor for any ultrabook, and many of the laptops mirror Apple’s devotion to slender, simple, shiny computers. Second, despite their light frames, they’re still most closely related to laptops than to tablets and run full versions of Windows operating systems instead of mobile software. Finally, they have a fairly agreeable price point, though I’d hesitate to call them “cheap.” Most more or less match the MacBook Air, ranging from around $900 to $1,500.

Ultrabooks are pleasing to look at, but before you spend your Christmas money on a model, there are a couple of other things to consider. For one, if you use a lot of physical media such as CDs, DVDs, and flash drives, then you may want to reconsider getting an ultrabook. To preserve their dainty silhouettes, these devices have to give up disk drives of any kind as well as a variety of peripheral ports. Most have between one and three external ports. For example, Vizio — branching out from its usual product line of televisions — has introduced two “Thin and Light” laptops with room for two USB 3.0 drives and a full-size HDMI port.

There’s also the price to consider. Right now, the ultrabooks on the market are competitive with the MacBook Air, but companies will likely undercut each other to get a piece of the demand for ultra-portable computers. Analysts had expected that the notebooks would be priced more competitively — in the $600 to $700 range, according to Ovum analysts — but so far, the majority of the laptops have been  hovering near the $1,000 mark. Also, Intel has previewed interesting features that will further distinguish ultrabooks of the future from the MacBook Air, such as Microsoft Kinect-like motion controls and voice-recognition control, thanks to a partnership with Nuance Communciations.

Ultrabooks could prove useful, however, for people who like the creation power that they get from a keyboard, as opposed to the largely one-way flow of information that they get on a tablet. It’s early to tell if ultrabooks will be a CES hit that translates into consumer buying habits for the rest of the year, or if they’ll end up like last year’s hot gadget — the tablet — as a market that’s just starting to find its legs a year later.

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