MyBB Community Forums

So - I want to create a system, with user profiles, registration, and essentially a community.
My goal is to provide a site for youtube promotion for a vast community of people who produce a certain niche of youtube videos. I was hoping to have a site like reddit, with categories, "following" users, and automatic embedding of videos. So, in comparision to reddit, it I want to post video X, I put the link in the link box, give it a title, description and tags, and post it. Then the embedded video is centered, and there's a discussion about the video below it. Alike an offsite youtube I guess you could think of it as.
Whats the best CMS, or code to use to do this? Thanks!

Oh, and how would a "Login with youtube/google account" be done?

Maybe this one ? http://www.phpsugar.com/phpmelody.html

Actually that's really good to know about, and only $40. Not bad.
I do feel though that it's a bit too much like youtube itself, by default. Maybe with some customization I could make it work though, thanks!

There you have some templates - http://demo.phpmelody.com/themepreview.php?themeid=3

Eh, still trying to find something.

PHPMelody doesn't seem bad though.

Still pretty confused about this.

There's soo many CMS now it's ridiculous and hard to weed through them all, I'm watching this thread so eager to see a suggestion better than sugar php for a video sharing based site.

Yea, well I'll use anything really, that just seems to be a good idea :3