3v3 means the other side will almost always have a healer. They're gonna CC one of your team, so basically it's 2 DPS vs. 1 healer, and you're going to have trouble killing anyone fast enough. You'll have more trouble since all your guys are squishy cloth wearers. You may have some fun in the arenas, and grab some arena-point-based gear over time, but I think it will be tough to be competitive. Occasionally, you'll hear the shaman folks talk about 3v3 some-- I've played some 3xShaman setups by myself in arena, with some small success (think 1625 rating), but it's a crapshoot and I'm not really competitive.

It's not that we don't talk about these adventures, it's just that most of us aren't very effective in 3v3, unfortunately.