While most of the Q&A about ASP.NET happens in the forums, I also receive a number of direct questions from users (and so do other people on the team). In most cases, I try to convince the sender to post to the forums instead, and there are a couple of good reasons for it. And no, the reason is not to just get rid of the user! :-)
The first reason is that posting to the forum gives you a much larger audience of people who may be able to answer the question. The answer may come from one of the Microsoft folks who are active there, or from one of the many experienced users from the community. As a result, you're much more likely to get a quick answer than by sending a private email to one person.
A second very important reason is that posting to the forums builds up the general knowledge base. Your question and the answers that it receives will be searchable by others for years to come. So asking your question there can effectively save others from asking the same thing. Or maybe their question won't be exactly the same, but it will be similar enough that they will post a new question that 'builds' on the previous answers.
Of course, there is no guarantee that every question you post will get answered instantly in a way to fully solves it, and it may take a few iterations to get it there. But it is your best bet!