In live ring games, I probably play hold 'em 90% of the time. That's not because I like it so much better than the other games, but just because my home club, Bay 101 in San Jose, doesn't spread a lot of other games. The only Omaha 8-or-better to be found there is usually "no fold'em" 4-8, and the only 7-stud is usually also 4-8. There's no stud 8-or-better at all. Because I usually play at higher limits, I rarely get to play these games when I'm home.
I do play them in tournaments, used to play them a lot in private games, and do play them when I'm in clubs in other parts of the state or country, so I'm not a piece of ripe fruit ready to be plucked when I sit down in these other games. I'm just not as good as I am at hold 'em, because I play so much more hold 'em.
At the TOC, I had to play stud, Omaha 8-or-better, and hold 'em in alternating rounds, and I expected that the hold 'em rounds would be my most favorable ones, because it was my best game. I quickly found out that I was wrong: while hold 'em was indeed my best game, it was also the best game for the vast majority of players in the field, especially the weaker ones.
There were a LOT of TOC entrants who, when it came to 7-stud or Omaha 8-or-better, couldn't play dead in a cemetery (a nice line, but it's not mine; I overheard a World Series of Poker player mutter it as he exited after a bad beat put on by an opponent who went on to win the tournament). As a result, even though I was not as skilled in these games, I made most of my profits there, and got into the money almost exclusively because of money more or less handed to me by players who were out of their element.
Does this mean you should start abandoning your favorite game in favor of others that are spread more often? I wouldn't go that far, not even if an in-the-money finish at the TOC or other multi-game tournament (the Legends of Poker, currently running at the Bicycle Casino in LA, will be offering a HOSE-hold 'em, Omaha-8, Stud, and Eight-or-better Stud) event August 22) is your goal. But if you have serious poker ambitions-be they in tournaments or in ring games-you probably should expand your horizons.
One reason why is the points race often offered in longer tournaments. Someone who plays only hold 'em or only stud will probably never have a chance to earn enough points, playing only those events, to win an overall points championship. But since most of my readers probably don't have their sights set quite that high, you should understand that more and more of the bigger ring games are also HOSE or HORSE (which is HOSE with Razz added). A one game specialist will get chewed up in such games.
Even if you just consider yourself a recreational player, I think it's important to play more than one game. In home games, there are often terrific opportunities to play weaker opponents in dealer's choice games, but more importantly, venturing out from your one-game "comfort zone" will help you learn how to "think like a poker player." Instead of playing by rote-as I see so many limit hold 'em players doing-you'll need to think and analyze more, and that process should help you when you return to your main game.
Think of it as the poker equivalent of cross training.
Venturing out of your comfort zone will also help you get away from dangerous thinking like "I know it all," and may put you in a position where you're more open to learning, even in the game you think you already know.
But the biggest reason of all to consider cross training, I think, is that going out and playing these other games will keep you focused on poker's relativistic nature. Most players are so focused on their own cards, thought processes, skills, and results that they forget poker isn't golf. Poker isn't you against the course. It isn't you against yourself (although your battles with yourself are critically important). It's you against the other fellow's cards, thought processes, skills, and results. If you can get away from thinking "me, me, me," and move towards thinking about "him, her and him," you'll probably find your results improving in every game, and at every limit.