Signs of Early Potty Training Readiness?

1) Jonah maintains a dry diaper during the night despite a fair amount of liquid intake.

2) He likes to play with the toilet flusher when he's in the bathroom.

3) He also seems to like the toilet paper.

4) The other night when I left a little naked Jonah for ten seconds to put his towel in the bathroom and set his plastic tub in the big tub, I came back to find that he had pulled himself up using the diaper pail and decided that was a good place to relieve himself, as if he somehow knew that was where his pee was supposed to go.