Yeah, the thing does wobble a bit, and then it cuts. That ending was one of the reasons I loved the flick so much. Nolan obviously knew that it would drive people nuts and start a conversation.
I think it's pretty obvious that he's still in a dream, tho, considering the fact that his kids are still identical to the kids in his dreams, despite the fact that it's supposed to be several years later. I think the fact that the thing starts to wobble is less a clue to the ending and more a clue to the whole movie. It's his totem and his dream. If he wants it to topple, he can make it do so, right? The entire movie could have been a dream.
If you think about it, the world he and his wife were in for "years" was supposedly at least a few levels in, right? And they were obviously still using their own familiar places at that time to construct their dream worlds. That's why he stopped doing that after his wife freaked out about it not feeling real. The problem with them experiencing years inside the dream is that when they 'died', they weren't shown waking up through several levels. Just one. Maybe it was meant to be implied, but if they spent years down there, what are the chances that they actually got all the way out? Maybe his wife actually did wake herself up.










