An interesting question and conversation, however I have not seen the answer to the question I always ask as I sort through seemingly endless fan requests or referrals (and that is not an "ego" thing - at least half the invites are people/places I've never heard of) - "What's in it for me to be your fan?"
If I know and respect you or your company, I'm happy to be a fan - I will probably have fanned you before you can invite me. But as a local business, potential prospect, or typical resident, why do I want my name on your page? All too often, (and this is true on Linkedin as well), I get a generic email with no personalization and no "WIIFM". The more personal the request, the more likely I am to pay attention; and I think that is the case for most people.
When inviting a local business, maybe a quick sentence on median income/buying power of my residents or average length of stay; for a prospect, mention several benefits as told to you by your residents or even a short quote from a happy resident; and for your residents, a statement about how supporting your fan page will most likely result in them having better neighbors (well, it could happen . . . !)
Thanks all for the good ideas! Doug