For New Stack Exchange sites (not SO, SF or SU.)
As a moderator on a new SE site (WordPress Answers) I'm pondering how to get more people to return and accept answers and to then continue to participate. Unlike most of the constituents of SOFU for whom SE has become ingrained into their lives many of our users ask a question and then never come back.
One thing I think would improve it would be if the OPs got an immediate email notification that their question had being answered (which they could opt out of when they ask the question.) I also think it would be helpful if there were email notifications after a week and after a month that said (with single-question and all-question opt-out, of course):
It's been 7/30 days and you've not accepted the answer; can you come back and accept an answer, or would you like to add detail in hopes of getting a better answer?
Both of those solutions just mentioned would take Jeff and Joel to agree and then implement which I fear is unlikely. So what other things can be done to get users back to the site after they've forgotten about the question they left unaccepted?
P.S. I asked "Okay for Moderators to Email People with Unaccepted Questions?" and @Pekka suggested I ask this question instead.