A few years back there was a wave of interest in card counting, specifically the antics of the MIT blackjack team, largely sparked by the book Bringing Down the House, later made into the film 21.
Though based on fact, Bringing Down the House and thus 21 employ a substantial amount of artistic license, so while the methods of card counting get an airing they’re really something of a MacGuffin for the Pygmalion-esque transformation of Jim Sturgess’ character from broke MIT geek to Vegas high roller. It’s a lightweight frothy romantic-comedy-thriller-heist-type film, the young leads are charismatic enough, especially with the more heavyweight backup of Kevin Spacey and Larry Fishburne; nobody really needs to get out of first gear with pretty one dimensional characters. There’s a bit of a twist to give our requisite happy ending, but it’s somewhat Ocean’s Eleven-Lite (when it’s not as if Ocean’s Eleven is that heavy in the first place).
Fun enough for a throwaway film, but if you have more of an interest in the mechanics of card counting then the Horizon documentary Making Millions the Easy Way is worth a look.