It's hoped there will be gazillions of apps created for it; like the iPhone SDK launch, but there's even more crazily optimistic people hyping this. Quite frankly, I'm much more interested in it as a compatibility layer for running Android apps, than as a replacement OS; I haven't tried it yet, so maybe it will be better, maybe worse. The good thing is, right now it's runnable as a chroot environment. That's very good news if you just want it for running apps, just like the Debian chroot stuff some people here are playing with. But it seems you do need a custom kernel, anyway, which is not so hot.
Sorry but can someone just tell me what the heck is Android? I've never heard of it before.