I agree with Flying Ron that content needs to be monitored.
You should have a clear list of rules, a disclaimer, and, again, careful monitoring of your site to prevent obscene and defamatory content from being posted and to prevent the content from infringing on copyright, trademark or privacy rights. You must be especially careful with trademark rights of college and pro sports teams, as these rights are vigorously protected.
You have your specialized forum topic already, which is important. You could check out [url=http://www.phpbb.com]phpBB • Creating Communities Worldwide[/url] and [url=http://www.vbulletin.com]vBulletin - Instant Community[/url] for forum script. You will need a webhost that can accommodate your bandwidth and web space needs. And you will need a good marketing scheme to draw people to your site.
Because you will want your forum to be user-friendly, do some research by checking out other forums, to see how they operate. Adopt for your own site the features you most like.
Once your site has a good draw, you can look into adding ads to help pay for your site.
Good luck.
