I know some overzealous but well meaning tech writers don't believe the first video of this rumoured Apple Tablet OS variant is real but here's a second video, more clear and with strange hardware in the foreground.
Note the strange desktop like environment running iPhone apps floating in independent windows. Someone on the MacRumors forums claims this is the dev kit. Hate to say it but this is starting to smell good enough to be fresh from an oven in Cupertino. Or at least I want it to be. I'd say this works for me as a tablet version of OS X. Of course, I can't be sure, but I'm sure as hell not going to dismiss it out of hand because I think it should be different.