What is the best way to tell members of a forum that the site is closing down? How can you let them down gently without causing too much distress?
Well, if the community is closing, it's clear the members don't really give a hoot. Let's say that, if you have at least 10-20 ACTIVE and committed members you won't close the forums, because you'd have quite some serious activity. If they cared about the forums, they'd be active. If they are not active (thus having you close down the community), I don't see why they'd be distressed: they stopped caring long time before. So I'd just close down the forums and that's it.
You cant be a gentleman in this stage,if your community is huge it would hurt more than you thing ,but if its small then no problems at all!
Despise the lack of interest, I think it can be still worth to be a bit of a gentleman about it. I think the best you can do is to announce your intentions and a closing date. The best way that it has been done to me as a member was to receive a brieft email alerting me about the possible closure in that date, encouraging to post my opinion on the matter and giving a link with the announcement with proper details. If you want proper results to consider no closing it say so, but also it is good to try to explore what things could be putting your members off from posting in the first place. If there is interest - yahoo! - use it to try to get a kick back into motion, if not... you did all you could and can feel tranquil about it. I think is very rude to find a community closed or in maintenance mode without giving before hand any kind of warning, some people do get busy and it is a big slap to come back to find that.