Here's my situation, which I think is pretty good. My wife is happy when I find things that make me happy.
Right now, I'm writing an iPhone app. I'm really jazzed about this, and I'm spending a decent amount of my leisure time working on it. My wife is excited that I've found something that's this exciting to me. She doesn't care about the app, she's not even potential user, but she likes what this passion does to my attitude, to my level of happiness, to my drive to succeed.
She is also interested in things. I have NO IDEA why anyone would be interested in those things. But I see her eyes light up when she talks about them, and that makes me happy. I like the fact that all I need to do is make a few dinners, take care of the laundry, and she can spend a little extra time that week doing the thing that makes her joyous and she can come home and share it with me.
On some days, the thing I do that excites me like that is gaming. Sometimes it's cooking. Sometimes it's programming or something else. But she and I both have our independent interests and our relationship works because we both recognize that and enjoy helping the other find the coolness.
You need to be responsive to your partner, as people have mentioned. If you're gaming to the exclusion of all else, that's a problem. But there's always room in people's lives for some hobby, for an avocation that really gets them going and they're passionate about. If your partner is opposed to that, you're in trouble. If you can find a way to make room for it in your relationship, it'll work out. I think that's closer to a "grown up" way of doing things.