In previous versions of Google Video, the right menu had links that said "Send link", "Put on site", "More from this user" and "Related". Now we have links that say "Playlist", "Details", "Send", "Embed", "More from this provider", and "Related".
Besides the renaming of some links, there are a couple minor changes in functionality. I assume the playlist attempts to automatically populate itself with videos related to the one you are currently watching (refer to the elevator disco video -- it could use a bit of improvement). These "related" videos in the playlist are streamed back to back without any action from the user.
Another addition is a details view that shows various thumbnails from throughout the video -- clicking one will take you directly to that point in the video.