i don't know if having a list to choose from would be the best answer. there are so many different topics that come up within posts that it might be a logistical nightmare to try to categorize them. rather than a dropdown box, it may be easier to implement a freeform field to enter a short description of what category the author believes it fits in. then, the post title and category could be shown.
i do agree that it would be a tremendous help for people to give posts as descriptive a name as possible. when i'm looking through Newest Nodes, i only look at postings that i feel i can answer or that might be informative to me. i'm a lot more likely to click through to a question about interesting flaws in regex (excellent discussion, BTW) than i am to visit something called "help" or "problems".

just my 2e-2