Users will be able to post links to downloadable and streaming content. As well as general NSFW discussion and topics. Is a forum like this technically illegal? Can I be pursued by the big adult movie companies? Should I incorporate? Any advice is greatly appreciated, Thanks!
You should first find a good host. One that supports Adult content for example. I'm sure you will find a good one. If necessary get offshore hosting
If people are posting links to copyrighted material, the adult industry can go after you. If you read and abide by all of the terms in the DMCA safe harbor provisions, you should be safe from losing a lawsuit. Register an agent with the US copyright office Remove content as soon as you are notified of offending content Don't promote or tolerate the use of infringing material Don't earn money from pages with infringing material That being said, if they are only linking and not embedding, those measures may or may not be overkill. I say this because the courts have not really decided the issue of linking to infringing material. However, if you follow the safe harbor provisions (do some reading), you should be good no matter what the outcome of this will be. Also, you should do some research into adult sites in general and make sure that you comply with all of the measures there.
Dropping a few bucks to speak with an attorney might be some cash well spent. Better to get some solid legal advice up front rather than find out some bad news after you get the site rolling.
Exactly druidelder, people seem to forget you can still be sued and charged if you reside in a country that enforces those copyright laws (such as the US)