Anyone running a PAID social networking site? Think Facebook/Myspace/Wordpress all in one

I'm trying to find the best platform/framework to run a paid social networking site on.

This is going to be sports related, where teens/young adults (or parents) can create a page to "show off" their accomplishments, share with friends, grandparents, etc.

The user gets their own "page" where they can edit, post pictures, link to videos, etc. If possible, I would like social networking functions as well, like groups, friends, etc. Also would like plugins like twitter, etc. (I know, I'm asking for a lot).

I would prefer users pages to be like www.domain.com/johnnyspage

This has to all be behind a payment gateway, however... a yearly subscription service.

I've looked at elgg.org, but it is lacking payment.

I've looked at Joomla, and it is the most promising so far.

I've looked at Wordpress MU, and would actually prefer it, but I'm not sure how to make it a subscription service where you pay to create your blog.

Any other options??


I'm not asking if you think it's a good idea... we have a niche, and we have a lock on that niche, so we're pretty confident the idea will fly. I'm just asking for technical suggestions. Thanks.