Poking more at the info Apple secretly registered iSlate.com a couple years ago, TechCrunch found Apple's possibly setup a shell company called Slate Computing, which has a trademark on "iSlate", registered to Apple's Senior Trademark Specialist Regina Porter, MacRumors discovered.
Regina Porter signed for the trademark recently - this past August - showing Apple's continued with "slate" beyond its initial registration for iSlate.com in 2006. And another trademark registered by Slate Computing in the US is "Magic Slate", which follows the same naming convention as Magic Mouse, obviously. MacRumors wonders if it might be something like a multitouch trackpad for computers (which we've wanted for a long time).
Whatever's going on, Apple's obviously gone through a lot of work to discreetly register a whole lot of "slate" stuff, which seems like a ton of effort for nothing, or simply a ruse to throw people off. It's funny that everybody "knew" what the iPhone was going to be called years before Steve Jobs took the stage to announce it, but no one really knows the tablet's name. I've always figured that, whatever it is, it'll have just two syllables. iSlate fits the bill. And for now, it's the only one with any evidence. [MacRumors, TechCrunch]