Convertibles lie closer along the spectrum to notebooks than tablets in that their keyboards remain attached, but PC vendors will primarily employ a range of hinge tricks to allow the devices to be held like a tablet. These devices will tend to have larger screens and because of the inability to detach the keyboard, will be heavier.
Some of the earliest Tablet PCs embraced this design philosophy, many with a single rotating hinge upon which the display was twisted to convert from closed clamshell to exposed display. This also allows the device to be used for presentations in open clamshell mode, although this has always seemed like the computing equivalent of the goofy Blind Man's Bluff poker game where players keep a card on their foreheads.
Back at CES 2012, though, Lenovo showed off one of the first Windows 8 convertibles -- the Yoga. The unassuming laptop uses a 360-degree hinge to fold the keyboard behind the screen, which disables input from the keys and trackpad when so positioned to prevent accidental entries. Meanwhile, Dell has beefed up the processor and screen size from its Inspiron Duo netbook to create the 12-inch XPS Duo designed for Windows 8.
PC vendors consider these tablets -- and they can certainly function as one. However, they will also be bundled with detachable keyboards, some of which may have the ability to charge the tablet when docked and many of which will lock into the tablet for a secure carry unlike many iPad options. The ASUS Transformers have pioneered this approach with Android, but such a path will be less of an exception among Windows tablets. Indeed, HP has already shown off the Envy X2 detachable tablet that locks into a matched keyboard. It's a convincing ultraportable notebook impersonation given away mostly by a bit of a hump at the hinge.
As always with PC tablets, just as with today's iPads and Android tablets, you'll be able to roll your own combinations as well, piecing together cases, stands and Bluetooth pointing devices and keyboards. But there should be less need to do so for those who want to seamlessly switch from desk to duvet. Indeed, these kinds of devices may be the best showcases for Windows 8.
The iPad was introduced as a device that bridged the gap between smartphones and notebooks. Hybrids don't really aim to fill the one between tablets and notebooks, but rather extend each to serve more of the use cases of the other.
Ross Rubin (@rossrubin) is principal analyst at Reticle Research, an advisory firm focused on consumer technology. Views expressed in Switched On are his own.