I don't understand who decided that the UI for Skype 5 was good. It sucks in so many ways. I'm using iChat a lot more these days now that most of my family and friends have Mac's, and while not perfect, it at least stays out of your way as a communications client should.
@JoeJoomla explained it nicely in a comment on an article in Rocket Theme about hacking the Skype theme:
I just updated Skype from version 2 to version 5 and almost fell off my chair when it started up. I thought I was being attacked by an IMAX Theatre...
Unfortunately, now that Microsoft owns Skype I don't see this improving any time soon. Microsoft doesn't have a track record of good UI (think the ribbon and why it sucks), so I'm not getting my hopes up. For now I'm going back to Skype 2.8 for Mac and getting everyone I know into iChat.