http://meta.math.stackexchange.com/questions/4880/

The underlining issue is not particular to MO/MSE. There are users who want to have all of the questions they are interested and only those questions in one place, and the set of questions users are interested in varies a lot. SE's current solution is "tag sets" (http://stackexchange.com/filters/) which allow filtering questions over the entire SE network based on sites and tags. Any improvement over that or any major modification of the software is unlikely to happen easily or any time soon. (They like the uniformity of their software over their entire network very much, it simplifies lots of things for them and the users.)

ps: I personally like having separate sites (research vs. undergrad teaching) and I don't see any real benefit in merging them.

That said, this is all too hypothetical.

On the other hand, in both SE and SE2 by visiting a user's profile you can see a list of tags in which they have earned upvotes. So if you want to see a user's "specialty areas" it is not too hard to find that information.

(Incidentally, "specialty area" should be read as nothing more than the areas in which the user chooses to ask and answer questions; my profile is only loosely correlated with what I do in real life.)

So how would your suggest be any real improvement to simply "Migrate MO to SE2.0"? (something that I currently in favour of not doing, by the way)

MSE is too big in the sense that if you actively participate in the site you easily see that in a very definitive way, MSE has too many questions and it became very hard to browse it already. Oh, before you suggest I use filters and all sort of hacks, I am using those. MSE is too big.

What you suggest is simply put MO and MSE on the same site and same users repository. I think it is not a good fit. Much like active research is not usually done in high school corridors, and for a good reason my office is located in the mathematics department building, rather than the high school outside the university.

Furthermore, if you think that MO is too big then perhaps it is time to add such features as you suggest to MO directly, without forcing users to filter through dozens of homework questions per day.

It's been about six years since all browsers include tabbed browsing support. If someone has a problem opening another tab, this is unfortunate, but it probably hints that they will have a hard time coping with complex filtering as well. These users, if they are using MO right now, are likely to cease; and if they could learn how to work with such convoluted interface, they can probably learn how to use tabs in a browser to open two different sites at the same time.

• Why is a topology made up of open sets?
• Is the boundary ∂S analogous to a derivative?

"If the site should become populated only by super-advanced, highly technical questions" (JDH), we would lose this enjoyable educational aspect.

I do agree with Joel's point. I am certainly guilty of taking these sort of questions to MSE, more than once too. I will try to favor MO in the future.

The problems with this are two-fold:

• First, while such more sophisticated questions do get knowledgeable answers on MSE, and there are definitely talented people there, it seems to me that they would get more and better attention on MO than they do on MSE, where such question often have fewer views and votes than they would earn on MO.

• Second, the existence of such a kind of level of questions on MO is important for the success of MO in the long run, and losing them to MSE hurts the operation of MO. In order to succeed, MO must have a large base of particpating interested users, who are checking out the questions and making posts. If the site should become populated only by super-advanced, highly technical questions, as some seem to have advocated, then I would simply expect the site to whither, with fewer and fewer participants, since even knowledgeable users will find less and less of interest, and so they won't be here to answer those advanced questions for which they do know the answer.

Thus, I believe it is important for the robust livelihood of MO to retain a greater number of those questions on MO, and to redirect them from MSE to MO. We should strongly encourage the posting of solid graduate-level questions on MO. I would suggest that the undergraduate/graduate divide is the right place to draw the line between MSE and MO.

The importance of this issue for the success of MO makes me look upon it as an argument for the transition of MO to become a stackexchange 2.0 site, or whatever it is called, provided that we had a capability to move questions from MSE to MO. For example, perhaps users could vote to kick a question from MSE to MO and vice versa, much like voting to close. This way, advanced questions on MSE would find their way to MO, and we could more easily and more finely cultivate a difference in level between the sites.

However, it is from an MO persepective my opinion that a certain type of question that in my opinion used to be more present on MO, and I assume this is precisely the type that now might be asked on MSE, starts to be lacking on MO. What I mean are perhaps too vaguely described "solid graduate level questions" (not the most standard textbook-excercise question from some graduate Analysis or Algebra course but, quoting the FAQs emphasize mine, "the sorts of questions you come across when you're writing or reading articles or graduate level books"; in other words question that are a bit beyond what one can find in any book on the subject but questions that might come up when thinking beyond what one read).

I believe that, ultimately, it is the smaller number of this type of questions that causes the at first glance paradoxical situation that on the one hand some people say that the level of MO significantly increased while at the same time I see some (at the strict/high-level end) users say that MO used to be better.

I'm not aware of MSE attracting a high number of research-level questions that don't originate from Akhil Mathew, Qiaochu Yuan, or a few other high-level undergraduates here who, as a sign of (false?) modesty, have decided to ask their questions there rather than here.

At least as far as those two are concerned, I think that if MO requests that they ask questions here rather than there, they would happily return to asking questions here.