how about......

And I'm reaching a little here..

The community, as a whole, imposes it's own self moderation.

I do not mean the moderators getting actively involved.

I do mean, each and every member of the community moderates their own post along the lines of one simple rule.

And the rule is

AM I HELPING MAEMO5 AND/OR THE N900.

if the answer is NO, then don't post.

if YES, then do.

There seems to be no built in method to prohibit any thread, even duplicates, and I don't think i'd like to see automatic censure either. However, the community can impose it's own form of censorship. If you don't like a thread, then you don't post. "I hate the N900" isn't constructive, so don't post it, or don't reply to it. "OMG, another whining thread" isn't constructive, so don't post it, or don't reply to it. and so on.

IF, the community could do such a thing, then the so-called "whining" threads will not be the most active, and so they'll drift into obscurity and die. And, the search for helpful info would become easier.

This isn't a total answer, but it could get us part way there.

However, it's also possible that I dream a utopian dream, and it is the complaints, the bickering, the endless repitition of useless statements that will proliferate. I can still dream though, and it is in the power of the community to make this happen.