I think its very common. I know a ton of moderate standard chessplayers (international master standard) who are now focussing on Poker. For a decent chessplayer, poker is not that difficult a game to pick up. Of course, Poker can be highly complex but the learning curve to become a competent player is very much steeper in chess.

However, the key point is that the rewards in chess are utterly pathetic. The top ten players make decent money, but noone else. There is very much more scope for excellence to be rewarded in poker.