I recently asked this question on Super User, and a big discussion arose on appropriate questions. The issue came down to the new verbiage in the FAQ:
I had figured that the websites line was just about social networking software (which a case could be made for closing the question I asked), but Diago said that they were shutting down ALL website application questions. So I can ask a question about Microsoft Office or OpenOffice.org, but I can't ask a question about Google Apps. He confirmed this, and after I pointed out that 34 pages (x50) of hits when you did a Super User search on "google", he said that they would all be closed as they came up on the home page. Notice that with other website type questions, you're probably looking at 20% of Super User.
for an increasingly large percentage of users, the desktop application is already dead.
So why is the new Super User moderator policy to marginalize these questions, and is it a good decision?
I think it will only hurt them in the long run, as they fight a software trend that is only growing more and more. I've asked a few website related questions on Super User, and have always been pleased with the quick answers that have come forth. I think website application questions are very relevant and should be allowed. The only difference between web applications and desktop applications is what's running the interface. They're both software that has to be used, and therefore the same type of questions come up for both.
We don't need to be fighting the future in our quest to clean up Super User.
EDIT: I just had to ask a question about the Opera Mini browser, but I wasn't sure whether questions about browsers would be allowed, so I had to ask it on another site.
EDIT3: I've just received the email from Jeff that states that the moderators are doing what he wants. He can edit this post if he'd like to post more information on his point of view.
End of Bounty EDIT: I don't completely agree with any of these answers, but I will pick Diago's since I feel it is the most complete, though I do think the percentage of web-application questions is higher than 1%. Time will tell on all these things.