Poker is more skill than luck. A study of over 100 million real world poker hands for real money showed:

Of the hands they examined, slightly over three-quarters of them did not go to showdown. That means that over 75% of the time, the best hand was not shown down. With that in mind, it can be said that skill was utilized instead of pure chance. That includes the skills of betting, being aggressive, and also knowing when to fold.

When there was a showdown, the study found that the best five-card hand actually won the pot only about half the time. The other half of the time, what would have been the winning hand was actually folded prior to showdown. This once again shows the amount of skill involved when players can get other players to fold better hands than them in order to win the pot. All in all, the study showed that the true best hand only won about 12% of the time.

Using that information, they argue that poker is predominantly a game of skill, being approximately 88% skill and 12% chance.

(Via Radley Balko.)