From Wikipedia:
I'll go along with what Nolan believes.
However, and I just watched it again last night, I can't get past the kids being the same age and wearing pretty much the same clothes. Also, Mal and Cobb got out of limbo by doing the train thing, but they jumped straight into reality? Shouldn't they have jumped back to the secondary/tertiary dream, and then needed to wake up from those? But that could just have been done to be quick and efficient in storytelling.
At first I was really annoyed at the ending, but after I read what Nolan says is the point of the scene (that Cobb doesn't care about the top), it made it sit better with me. Still, it's a fantastic movie that feels so cathartic to watch, especially such a strong emotional end with the swelling melancholy music.