I wonder how long the internet will be around before the handful of people who are like, "hahah you're on the internet, you four-eyed geek" stop doing that! A song about a messageboard is no different to me than a song about, say, a venue or a local scene or a town, or whatever. It IS an entity that exists.
In regards to Ben Weasel, I'm pretty sure this song was written when he was still on the PPMB and super into it. It's a pretty old song!