WordPress MU

I haven't actually started using WordPress MU, but I want to verify that I can accomplish what I want to do.

I want to create multiple 'Social Networking' sites on sub-domains via WordPress MU and BuddyPress. So just one domain (ie. http://www.thisdomain.com) and different 'Social Networking' sites on site1.thisdomain.com, site2.thisdomain.com, site3.thisdomain.com, etc. Each sub-domain would have different members (actually...all the different sub-domains might have the same membership). Each sub-domain would definitely have different administrators or 'owners' of that social networking site.

Does the above make sense and is it possible? I think it is from what I've read so far....

Yes, it is entirely possible. You'll just want to select "sub-domain" during the WPMU install process. Users can be members of any blogs or none at all. It's a very slick setup.

Buddypress work son the whole entire site though. So if a user is a member on the main site, they're a member on all sites.

Go to http://testbp.org and sign up to give it a spin.

Thank you so much!! I thought it was possible, but just wanted to be sure before I started the whole process.

Ok tim if I did not select subdomain during the install process how do I fix it.
other than a reinstall.

Subdomains are selected by default when you install. Did you select subdirectories?

If so, and you really need subdomains, AND there's no member blogs (or just test ones you can delete), then you have to edit wp-config.php. Find VHOST=no. Change it to yes.

You also have to edit Apache and your DNS records to setup wildcard subomains as outlined in the readme.txt.