Ha! It would be nice. But it would also be frustrating, because your Fannish Guardian Angel doesn't just tell you stuff; they steer you around it by other means. I woke up without any interest in that fandom one morning, which kept me out of its eventual devolution, but I still had all my fic subscriptions (come on, FGA, can't you unsubscribe me from WIPs at the same time you deleted my interest?), not to mention I'd already bought two seasons on DVD, and I didn't have a replacement fandom ready to divert my interest to so I ended up bored for a while.

So your fannish angel would probably keep you from starting a WIP by crashing your word processors, keep you from commenting on a post that will turn wanky by making you get home too late from work to see it, and remind you to start your exchange fic by making it the exchange the absolute only thing anybody on your flist is talking about, or something. :D Convenient in the long run, but annoying in the moment!