I know that this has been brought up before. I know it was previously declined. And while I agree that it certainly can be abused by the userbase ("Problem running Windows, please help!!!11!1") but on rare occasion, we will find that the word "Problem" is in the title of a tool or program and cannot be avoided when asking the question.
Here's a screenshot: Note I see this in Windows 7 IE9 and Chrome. I don't have Firefox and I don't want to install it.
They got around it by using unprintable characters. However, they still show up as squares, making the question look all funky.
I realize we don't want to open the floodgates with this restriction, but at least allowing a moderator to edit the word into the title would seem like a good compromise.