It's not a huge selling point, but Kwolla also gives users some basic statistics and analytics on their profile. It also handles conversion of video itself with

It's not a huge selling point, but Kwolla also gives users some basic statistics and analytics on their profile. It also handles conversion of video itself without having to first upload it to Youtube. Elgg would be the PHP version, it's free and open source. The code is very poor and it's hard to author on. Kwolla is very clearly written and easy to write modules for. The two biggest paid competitors are Ning and SocialEngine. Both have more features, but are more expensive. Ning is hosted and not as customizable (since you don't have the source) and SocialEngine is more expensive (but it's an impressive product nonetheless).