I don't think that easter eggs are anything to complain about. I don't think that they are a waste of time, effort, or resources. I think that they are merely an acknowlegement that the programmers and the users are still both humans, and there should be no reason why people can't smile now and then while using Excel or Visual Studio. That's just my opinion, but I think that it's nice to, now and then, have a reminder that real people work at Microsoft.