Abraham has been able to roll from his back onto his belly for quite some time now... probably since he was about 4 1/2 months old. This past week he has been both turning in circles on his belly, and then flipping over from his belly onto his back again!
He's still kind-of slow about it, but he's beginning to understand that he can move himself to get someplace. I set his giraffe (his favorite toy - it winds up and plays a song) on the other side of his floor blanket, and he was able to roll from back to belly to his back and finally to his belly again to reach it. He's growing up SO fast!