Spence,
The nice thing about a three handed game is, if the players don't like it, they won't participate. I would say, if the players enjoy the game and the house can find a way to run that type of a game profitably, why not? You might want to establish your own set of rules for your 3 handed game. There are some issues that could arise that would warrant special attention. The game should stop if one player takes a necessary break, for example.
Who knows, you may be creating the next new game!