Your question would probably be appropriate at one of:
http://math.stackexchange.com/
http://cstheory.stackexchange.com/
This site is for research-level questions, in mathematics itself, that are likely to have short well-defined answers. "Research-level" means, roughly, questions that might be discussed between two professors, or between graduate students working on Ph.D.'s, but not usually between a professor and the typical undergraduate student. It does not include questions at the level of difficulty of undergraduate homework.

Unfortunately, your message implies an incorrect claim that cstheory.stackexchange.com allows non-research-level questions. Please do not include cstheory.stackexchange.com in a list of the sites suggested for non-research-level questions. I do not know if this is related, but we are currently observing an undesired increase in the ratio of homework questions at cstheory.stackexchange.com. Please see a discussion on meta.cstheory.stackexchange.com for more information on this.

The point remains -- if someone bothered to analyze whether various prominent mathematicians on mathoverflow registered before or after asking their first question, I'm convinced it would be clearer that such barriers are dangerous.

Also, even after reading the article, I don't see how MO has jumped the shark.

If we can get Grothendieck to start visiting, then MO will have jumped the shark!

The problem was that it was (and still is) not currently possible to do this through the SE software (and therefore it would have to be hacked).

Thank you, Gerhard. All confusion had been cleared. Like Will Jagy says: no actual disagreements. Crisis with infinity (this one, not the set theory one) averted.

(I'm not trying to argue or anything. I am just trying to figure out what you want to say. I think you meant the first of the two options, but the phrasing is a bit ambiguous.)

Thanks for doing that.

Evidently we agree on the actual point. I'll remove that tangential edit above for clarity.

Whether or not we ever reach a conclusion on this elitist/politeness business, I think the phrase "MO-level" should be eliminated for at least the argument above.

Now, about politeness: it is a lot easier to offend on the internet. And it is also a lot easier to take offence on the internet. This is of course due to the oft-observed triviality that the textual nature of the communication eliminates contextual clues, which we sometimes try to reinstate by inclusion of smileys. Since this cuts both ways, I think, in general, barring overt rudeness, it is hard to establish a "suitable level of politeness", especially considering that individuals of different generations tend to have different perceptions on what is and is not appropriate to say on the internet.

Which is all just my way of saying that I disagree with the premise that MathOverflow should have a "polite interface" with the public, where "polite" is taken to mean "smooth" or "showing regard" or "deferential to". I agree, however, that we can be at least "polite" in the sense of being "civil". Which means that while I find it unacceptable to say a question is too "simple" or "easy" or "trivial" for MO, I also don't see it necessary to sugarcoat our message that MO is for discussing mathematics one is likely to encounter in one's post-graduate mathematical education and thereafter.

(An aside to finish this longish post: @Gerhard Paseman: you do mean the "Mr. or Ms." in a tongue-in-cheek way, right?)

Tate won the Abel prize earlier this year. I think that people can be justifiably proud that an Abel prize winner has participated on MO (and that Fields medalists also participate); it is (not the only, but one) measure of success for the site, and it is reasonable to try to think about what aspects of the site contributed to this success, and (at least) be sure not to damage those aspects too much.

Regards,

Matthew

If you are the person to cast the final closing vote on a question for the reason that it is not MO-level (or in general for being of no interest to research mathematicians at all), would you also be so kind to re-tag the question to [tag-removed] so those of us who filter that tag can benefit from your efforts?

I know Yemon and I (and possibly some others) have been removing tags for such obviously inappropriate questions when we see them on the front page, but this will of course bump them a little bit and cause them to stay longer on the front page. It would help if the re-tagging happens closer to when the question is closed. Thanks!

Note that I said the concept, not just the terminology: if you asked them to describe to you what kind (or level, or whatever) of problems a research mathematician works on, they would either have no idea or very mistaken ideas.

So I don't see an easy fix here: we are trying to tell people that this site is for math questions at a level beyond that which they have any prior experience or real conception that math questions can be. (Now there's an elitist sentiment! But it seems to be true.)

Deane, I like that one too. I don't think it is impolite. Neither is talking about «MO-level»!

I usually don't write "MO-level". I think the wording I prefer is that "... your question does not fit into the scope of MathOverflow." Or sometimes "this problem is ill-suited for MathOverflow".