If you want to cut down on Facebook clutter, just turn your profile into a limited one. For some reason that has the strong psychological message of "Don't communicate with me" even though they still can. I know two people who have done that, and they said messages and everything just stopped almost instantly.
And the whole app-spam is very annoying. Early developers are screwing the later ones by just inundating people with requests/invites etc which turns people off to the whole concept. But there are SOME useful apps available now, and hopefully more in the future... :)