I think it would be nice to have a comment template that everyone could use when a (new) user asks a question on the site which is clearly more appropriate for MSE. Here's what I've been using today:

MathOverflow is a question and answer site for professional mathematicians. I think your question would be better suited to Mathematics on the Stack Exchange network.

`MathOverflow is a question and answer site for professional mathematicians. I think your question would be better suited to [Mathematics](https://math.stackexchange.com/) on the Stack Exchange network.`

This is far from perfect. It would be nice to include a statement about the quality standards of MSE. As has been discussed before on meta, we should not migrate questions which are poor by MSE's standards. I'd also want to be able to give the user some advice what to do. Should they delete their question and ask at MSE or should they migrate the question? Either way, we should let them know how to do that.

Any suggestions? Any other features that should be included?

I have started using the following message:

MathOverflow is a question and answer site about research level mathematics. I think your question would be better suited to Mathematics on the Stack Exchange network which welcomes questions at any level.

`MathOverflow is a question and answer site about research level mathematics. I think your question would be better suited to [Mathematics](https://math.stackexchange.com/) on the Stack Exchange network which welcomes questions at any level.`

This doesn't address all the criteria I mentioned above, but I prefer describing the mathematics as research level as opposed to describing the users as professionals (I don't fit this description for example). Also, this is a little bit clearer as to why MSE is more appropriate for their question.

cannotdelete their question (which should be a non-negligible fraction of users asking the type of questions we are talking about here). Thus as a general procedure this cannot work. – user9072 Oct 6 '13 at 19:44notmigrated to m.se. – Gerry Myerson Oct 6 '13 at 22:40