AOL, which I had before it was connected to the internet, also had "screenames," profiles, chat rooms, private chat, emails and even file sharing! (I used to find and create midi files until they closed it down for copyright reasons).
While obviously all the technologies build off of the original start of the Internet, I'll agree that message boards really tied a lot of features together ON the internet itself... but just as Facebook has taken concepts from the "bulletin"/message boards, these forums are just an extension of concepts before them.
Also, RoD, you're thinking of
BBS. I remember, as a teenager, (again, before unerstanding what the "Internet" was), dialing into my friends computer and him sending me a copy of the Star Trek Generations script, about a week before the movie came out. I printed the whole 120 pages out on our dot matrix tractor-feed printer (which took hours) and read it before seeing the movie. I thought that was just awesome that I could do that (I still have it too... the paper version that is)