No. Never shameful. If I'm in a large group I won't, really. It's bound to alienate a few people.
In one on one, it depends. If it's a girl then I'll be honest. I'll talk about it for as long as she's interested (usually not long).
If it's a guy, I will talk to a degree, but I don't like talking about specifics. "Oh, this game developer X, and this physics engine Y, and that Microsoft, oh man." I prefer to talk about games that I either really enjoyed or really disliked and why. One of my favorites is recounting how much fun I used to have with the original Halo. True blue childhood gaming memory, that one.
The bottom line is, as long as you don't show any shame, they'll just accept it. If they can't, then that's their character flaw and I fully intend to give them **** for it.
Example: My boss at GameStop was a complete prick. He'd give any co-worker a hard time for anything he could. One day he asked me what I'd been playing all weekend. I looked him straight in the eyes and said "Maplestory. It's pretty fun." as if it was just a regular thing to say among gamers (it's not). He paused for a good two minutes then finally said "dammit. I really want to give you a hard time for this but I can't do it now."
People will feed on how you present it. If you act like it's something you're embarrassed of, they're more likely to enforce that.