Copyright/patent and Intellectual Property laws?

[Yeti]

If you're really starting a social networking site, you should likely be in touch with an attorney who can review what you're doing and look up things like related patents.

It's doubtful that simply having "followers" is patented, especially as it's a fairly basic function without any other realistic alternative. There might be some specific method or technique one site uses that's patented, but it would be behind the scenes.