While this is kind of old news since it wasn't announced at WWDC 2010, it is still important. Engadget posted photos of what they are claiming to be a large multi-touch trackpad accessory from Apple. It appears like the accessory would connect to computer's via Bluetooth and provide an extension to the trackpad or mouse on a Mac. It would support multi-touch gestures and maybe even handwriting recognition.
New images received with a claim that the device supports handwriting recognition in addition to "every feature you can find on a Magic Mouse (and possibly features of a MacBook Pro trackpad)." This, from a person who claims to be personally testing it.
The device didn't make an appearance at WWDC, but is was initially expected to.
