Perhaps, but I think for this particular market they had no choice but to launch big. Look at Orkut, their previous (dead) attempt at a social network. Facebook is extremely entrenched now, and there's little to no incentive to users to opt-in to something else. To attack the power of Facebook/Twitter, this was really the only way of doing it (although I agree, perhaps a Labs feature would have been a better way of introducing the concept for a couple of months at first).