"I mean what is this friend-trend about really - especially on a video site?"
Friends everywhere = the uploaders have their logo picture / link all around the site, on every people's page who is the user's friend. It means the uploader is getting the non-spam advertisement for his channel. You see a good avatar, you are clicking on it. If the channel is good, you watch the videos or you subscribe. Without friends list people get spam Private Messages and such. Who wants that? It's bad for everyone.
"I accepted about 2000+ friends via requests - in reality, a waste of page space (and server-space) as was meaningless."
That's free advertisement for your page. It helped you to read the 1 million view.
"Friends can do their 'thing' on Google+ or facebook. Surly that should be enough for them."
Not really. I need Youtube friends. How do you let people know you have a Youtube channel with videos and they probably would like it. That is the Friends invites about. I found a lot of great channels trough that. I got invites I visited the channel and I subscribed because the content was good. It has nothing to do with Google+ or Facebook.
New layout = terrible
Just read the comments, 85-90% of the users hating the new layout. If Youtube did a "good job", then why the 90% hating the results?