YouTube's most recent redesign cleaned up the interface a little, but it still has room for improvement. Toogles is a Metro-inspired interface that cuts out all the filler to focus on just the videos.
While we have covered plenty of ways to get rid of YouTube's biggest annoyances, Toogles does the skinning for you and makes browsing and watching videos on YouTube more about the videos than the social aspect. You won't find comments or ratings here -- just videos (unfortunately you also won't be able to log into your YouTube account).
It's an interesting alternative, and if you're sick of all the extra noise on YouTube, Toogles is worth checking out. You can also snag the Chrome extension to automatically route YouTube URLs directly to Toogles.