There is a new layout coming to YouTube and it is now up for testing and feedback from their users. Here are the screenshots of YouTube, the old layout and the new layout.
The Current (Old) YouTube Layout
The New YouTube Layout
I like the new layout personally, it is more organized and easily manageable if you have your own videos or simply watching.
If you want to test it out, just login to YouTube, watch any video, and click the “Try out the NEW (beta) version of this page!” link just above the video owner infobox.