The Grand is a pretty good, but not great, film. It's got some funny moments. I recommend it for poker players, and perhaps a general audience.
Don't expect a realistic portrayal of the poker world here (other than an excellent Benny Binion-based character): the humor is pretty broad and far out. I do think the best realistic parodies can be better than this film, but this is a welcome improvement on the awful poker films that have been produced since the boom started. You won't be able to figure out who wins the tournament because this is truly an improvisational film: they actually played out the tournament rather than scripting it. While the film was funny early on, I did find it slowed down later.
You'll recognize lots of people in this film, like Gabe Kaplan, Phil Gordon, David Cross, Richard Kind, Dennis Farina, Cheryl Hines, Ray Romano, and Werner Herzog (ok, most of you won't recognize him). I think Woody Harrelson turns in the best performance in the film. Shannon Elizabeth and a few well-known professional poker players do cameos.
I give it ****, which means above average (for a poker film anyway). The critics have given the film mixed reviews (see Metacritic). The small number of voters on IMDB so far give it high ratings.
The other poker films I recommend are The Big Blind (torrent), Rounders, and The Cincinnati Kid.