I like Cincinnati Kid as much as the next guy, but that last hand is completely ludicrous. No credible player would ever play those hands like that. All that being said, here is my top five list:
1. Rounders (yeah, yeah . . . but I love it because of Famke Janssen. Well, and Ed Norton is a great actor).
2. California Split (the depiction of poker is more realistic than almost any other movie).
3. Cincinnati Kid (hey, Steve McQueen and the supporting cast make for a lot to like).
4. Maverick (it's a western, and a list like this needs a western).
5. The Croupier (not strictly a poker movie, though there is one scene that allows me to shoehorn it in here, but it is a great treatise on gambling).