Games with lots of voice chat?

I just got a microphone headset and am playing Cod with it, but I'm kind of disappointed to find hardly anyone else has one. I want to use it to chat and actually try and use a bit of strategy in multiplayer, so does anyone know of good games with lots of voice chat?

Left 4 Dead has alot of chat, same with TF2. Though it's not always a good thing...

Team Fortress 2 definitely has voice chatter. Battlefield 2 has a lot of use of voice chat depending on the server. The mod Project Reality for Battlefield 2 has a lot of voice chatter.

All valve multiplayer has a lot of voicechat. Batllefield 2 has squad based chat so you can only talk to your squad. The reason call of duty dosent have a lot of voice chat is because most of the people your playing with are most likely kids or casual gamers who don't see the need to buy a mic.