It appears to have changed in the last few months, and it didn't show full history, so I'll take it back slightly, but you can still see other Youtube users favourites/subscribed: https://www.youtube.com/user/whoever
Some people have a link from their G+ to their youtube, but it seems not to be there for everyone any more.
Some people have a link from their G+ to their youtube, but it seems not to be there for everyone any more.