Ok I asked about the audioscrobbler plugin crashing over in the audioscrobbler forum and the guy realised he'd uploaded the wrong exe.

So for those who want to go back to using audioscrobbler with foobar, go back here and redownload the version 1.0 installer and all should be fine

ps audioscrobbler looks even better since they fixed the DB. if you haven't tried it yet, I encourage you to join.