I don't really have any comments on your question, but your "stand to gain points" clause gives me the idea that you think MO is a gigantic competition. I'll just remark that I don't think like that at all.

Personally, I never upvote a post that I think should be community wiki but isn't, no matter how good I otherwise think it is. If most people act the same way, I don't think this should be a big problem.

Polling the community, etc. It's usually pretty obvious when a question should be community wiki or not. Every post I've flagged was either wikified by the user or wikified by a moderator.

David White, you say you have seen many questions that are not CW but should be. Could you provide some examples. I specifically ask since there is what I consider to be a somewhat widespread misunderstanding regarding the current rules for CW; it seems to me they changed but I am not around for long engough to know this for a fact. It seems to me this is in some sense preserved in this 'CW hammer' terminology in use, somewhat along the lines: 'ok it is somewhat off-topic or soft, but at least CW, so no problem.' For all I know, this is not current policy according to statements of Anton on more than one occassion, here is a recent example

Indeed, somewhat recently I saw somebody (not you) quite aggressively asking why something was not CW, which in my opinion definitely should not be CW. Indeed, there are also questions that are CW from the start but should not be (according to my understanding). In particular, it is not true that a question being soft, on notation, on history or something like this alone makes it a CW question; it is only that question in this category tend to be such that they are CW for other reasons.

I have the feeling that many times this happens it is just a relatively new user who isn't really in the know about the whole deal with community wiki questions---even if they have read about them in the faq, it may have not crossed their mind when asking their question. To me it seems counterproductive and slightly hostile to downvote such questions. I'd be more worried about people taking reputation too seriously. In my opinion, it's not the end of the world if some new user gains a couple hundred reputation "unfairly". I also think people should try to refrain from judging the reasons why a poster doesn't make their question community-wiki. Sure, they might have done it in order to "get some reputation", or they could just be a new user. Seriously, it's not as if the little box with the term "community wiki" beside it is very compelling to a new user unfamiliar with how mathoverflow works. I would cut these people some slack.

(Aside: I probably received about 100-150 reputation "unfairly" when I first joined up from improperly community-wikified questions. In fact, it took me a while to figure out how the reputation system worked. Eventually I figured out that you don't get reputation from community-wiki questions, whereas you do from non-community-wiki questions. People uninterested in reputation certainly aren't going to pore over the parts of the FAQ explaining the reputation system.)

I never understood why community wiki questions and answers gain no reputation points. It is very interesting that people regard this software feature as some sort of moral axiom.

I agree with Shevek: cut new users some slack, and remember that not everyone is particularly bothered about "reputation".

Once you've used this site for a while, it's easy to forget how complicated it can look to fresh eyes. For example, go to the front page and count how many elements there are. By an "element" I mean something like a link, a tab, a reputation count, a view count, a datestamp, an entry box, a title, a menu, a name, a question, a tag ... New and newish users are highly unlikely to know what all these things mean, and similarly may have no idea what "community wiki" means. As Shevek says, the tick-box doesn't exactly jump out at you.

That isn't meant to be a criticism of the design of the site, which I think is pretty good. It's just a plea for some understanding of what it's like for new users. If a new user asks a good community wiki-type question and gets some "undeserved" points, what does it matter? Welcome to MathOverflow!

I also do not quite understand some discussion related to reputation. And, I think CW is rather over- than underused (and some CW question should not have existed in the first place). However, in some circumstances I think it is useful, and then it is also useful that there is no gain/loss in rep.

To me the typical example is a question where there are a couple of standard answers essentially everybody can think of and the only interesting thing is what is the distribution of the opinions expressed by votes and there is also no particular usefullnes in giving a similar but somewhat different answer; why the first to state the obvious should then get 'something' I think there is no need. And many of my downvotes were made resorting a CW-lists question; it would be strange if such votes had a rep-influence.

@David: I am confused regarding this issue now; but I defnitely was under a miscoception here and this behavior I am surprised about seems consistent as I checked in some case, so this is by design. Though I still believe that those answers appearing after the questioner decided for CW are automatically CW (without moderator intervention). But I agree it is odd if there are some 'old' non-CW answers on a CW-question, as this seems then arbitrary.

That's OK, I found myself trying to figure out what a country-western complex might be.

Thierry, I think your remark is very good. But I would like to stress that this is how (among others) CW is supposed to be used by those implementing it. Yet, this has in my experience very little to do with how some want it to be used, and it is frequently used. For example as documented by what Asaf Karagila and others wrote in what is linked to. Where the point is very clearly that they do not want that people gain reputation for not directly mathematical questions/answers, and it is this (IMO wide-spread) line of reasoning that Gil Kalai seems to refer to. For example, for many advice-questions I think it makes little sense to argue that this should be CW to make things easily editable; often the answers are personal testimonials or experiences, to have them significantly edited by somebody else seems less desirable than for pure math answers.

So while I understand well why CW is like it is regarding rep from the point of view of those that control this behavior (who have a quite different idea when it should be used, yet in any case very rarely), I find it much less comprehensible in view of the way it is often (ab)used. As said, I think CW is over-used. If the community thinks that soft-question is not good enough to give rep, it should IMO simply be closed not turned into some form of second-class status.

In my experience, which is limited as it is rare, the direct editing by others works well if OP explicitly invites it, via a 'feel free to edit/expand' or something like this. (Otherwise I agree it is perhaps too rare; but I myself am hesitant too to edit others postings.)