Top picks: The best Windows 8 tablet laptops, convertibles, and Ultrabooks

When Intel coined the term "Ultrabook" to describe a new breed of notebook -- thin, light, power-efficient, all courtesy of new chip set technology -- it was easy to dismiss as little more than a clever marketing ploy. But the units themselves, from a broad range of manufacturers, have turned heads and created a niche for themselves in the PC market.

Credit Windows 8 too for its part in spurring a general rethink of the laptop among hardware makers. By attaching a touch-driven tablet UI to the traditional Windows desktop, Windows 8 (like it or not) has given birth to a wide variety of tablet-laptop convertibles and hybrids. The result is more choice than ever for the Windows stalwart. As always, some options are better than others. Let this brief recap of InfoWorld's Windows 8 hardware reviews (so far) be your guide.

[ Windows 8 left you blue? Then check out Windows Red, InfoWorld's plan to fix Microsoft's contested OS. | Ease the transition from Windows 7 with the Windows 8 Deep Dive PDF special report. | Stay atop key Microsoft technologies in our Technology: Microsoft newsletter. ]

The new form factors
Windows 8 notebooks come in roughly three basic designs: the classic clamshell (the Lenovo X1 Carbon, the Acer Aspire S7), the convertible (Dell XPS 12, Lenovo ThinkPad Twist), and the dockable or detachable (HP Envy X2, Samsung Ativ Smart PC Pro 700T). The clamshell of course appeals mainly to those who are comfortable with a conventional notebook design and don't have much use for a tabletlike experience.

The second form factor, the convertible, is a halfway house for users who want a tablet design and don't mind lugging the extra weight of a keyboard -- or for those who fear that a detachable keyboard may become a liability (for example, if it's left on the train).

But the third form factor presents the strongest possible contender for the market currently dominated by tablets. Some dockables get battery life comparable to a tablet (even more if the keyboard dock doubles as another battery, as with the HP Envy and Acer Iconia W510), and provide the advantage of being full-blown Windows machines.

However, note that the dockable's battery life typically comes at the price of compromised performance. That's because most dockables are built around Intel's low-power Atom SoC (system on a chip). The Samsung Ativ Smart PC Pro 700T, which sports an Intel Core CPU, is the rare dockable that also qualifies as an Ultrabook.

Note too that dockables can suffer from an inconsistency of design and build quality that doesn't seem to plague the other form factors as often. For example, the dock of the Samsung Ativ Smart PC Pro 700T is remarkably shaky, whereas the dock of the HP Envy X2 (the class of the Atom-based dockables) was as solid as the rest of the unit.

To touch or not to touch?
If there's one feature Windows notebooks sport regularly these days, it's a touchscreen. The reasons for this are obvious, but also circular: Ultrabooks are at least partly in competition with tablets, so touch is all but mandatory.

There are Ultrabooks that ship without touch, though not many -- the Lenovo X1 Carbon and the Dell Latitude 6430u, to name two. Why? Target markets: such machines are mainly designed as business workhorses, and touch on notebooks isn't automatically a must in many business environments. Touchpads and nub mice generally work fine for such audiences. That said, note that Windows 8 has an edge over Windows 7 in terms of battery life.

Consequently, such machines ship with the option of either Windows 7 or Windows 8. While Windows 8 without touch is problematic, some manufacturers have partly made up for it by including gesture-powered touchpad software. The HP EliteBook Folio 9470m, for instance, has a touchpad that lets you navigate Windows 8 using the same gestures you would apply on-screen. Unlike gesture-enabled touchpads on other Ultrabooks, HP's is programmed with care to avoid having accidental gestures trigger its Windows 8-specific functions.