
For most people, IC is IC and OOC is OOC. They realize there's a great big world out there OOC beyond their role-play, so they're typically fine with voice chat or OOC chatter without it affecting their role-play. That being said, you'll find a lot of FC's and LS's like to voice chat regularly. But for role-play FC's, voice chat is almost never mandatory (outside of maybe their raid groups), and it's pretty baffling when it is mandatory, so I wouldn't worry about it. If you're looking for hardcore immersion, you're probably going to be joining heavy RP FC's and LS's, which will almost never demand that you voice chat.