I would hope Apple had a skunkworks team setup at least 2 years ago working on bringing OSX kernel to the iPad, along with a revamped touch UI.
If they do not, then they're screwed. I mean they're screwed anyway, because they seem to insist upon everyone using Objective-C which just ain't going to happen.
Google/Android is a mobile phone OS. It has no place on Tablet PCs. It isn't powerful enough. Java programming is dying a slow death. Google themselves admit they were caught off guard by the success of Android and that it presents them with a massive engineering problem (because it was only ever designed as a lightweight mobile phone OS, hence is hard to scale up). That's why they're looking at taking it to TVs because yes it would fit quite nicely there. But Microsoft is already working on future Xbox concepts in that market (see Dave Cutler, the creator of the NT kernel, moving to the Xbox team last month, and Microsoft only moves this most senior of their engineering fellows to a new department when they're planning something BIG).