Microsoft is taking a different approach with Windows Phone, trying to deliver the same user experience across all of its devices, this, and control, being the reasons behind setting out strict hardware requirements which are being updated on the go.
It looks like Redmond will use the same approach with Windows 8 tablets too, trying to guarantee a constant UX among all devices which will hit the market. These devices will either be tablets or convertibles, defined as follows:
“A tablet form factor is defined as a standalone device that combines the PC, display and rechargeable power source in a single chassis. A tablet does not include a permanently attached keyboard and pointing device but can be connected to a port replicator, keyboard and/or clamshell dock.”
“A convertible form factor is defined as a standalone device that combines the PC, display and rechargeable power source with a mechanically attached keyboard and pointing device in a single chassis. A convertible can be transformed into a tablet where the attached input devices are hidden or removed leaving the display as the only input mechanism.”
Just like in the case of Windows Phone, Windows 8 tablets/convertibles will need five hardware buttons: power, rotation lock, Windows Key, volume up, volume down (Windows Phone has power, back, Windows Key, search and camera). As far as display resolution goes, “the minimum native resolution/color depth is 1366 x 768 at a depth of 32bits. The physical dimensions of the display panel must match the aspect ratio the native resolution. The native resolution of the panel can be greater than 1366 (horizontally) and 768 (vertically).” And, while at the display, Windows 8 tablet/convertible screens will need to be able to recognize five touch points, one for each finger.
Slates that will be equipped with broadband radios will need an assisted GPS radio and those that will feature NFC will have “touch marks” to indicate the location where the contact should be made.
Other hardware requirements include at least 10GB free space after the out-of-box experience completes, WLAN and Bluetooth 4.0 + LE (low energy), Direct3D 10 device w/ WDDM 1.2 driver, 720p-capable camera, light sensor, magnetometer, accelerometer, gyroscope, USB 2.0, speakers.
There’s a link below that takes you to the official documents which define and explain in detail every aspect of what’s coming up. If you need to know other stuff aside from the above summary, make sure to check the documents out.