I don't mean to create unnecessary work for anyone (ie. Mith), but I've got two suggestions for improvements (and I understand a large amount of time may pass before they are acted on, if at all).
1. The search feature is a little strict. It rejects common words and words with 3 characters or less. This is somewhat restricting, as sometimes I have a 3-letter search term in mind, and I can't think of a longer alternative that would produce the same results. A Google search is nice and easy - you type in your keywords, and it has a go at finding them no matter what you typed. It would be good if the search behaved in a similar way to that (it's sort of a big expectation, I know).
2. I think it would be valuable to have a 'get new' link/button/whatever that restricts its searching to only the threads that you have posted in. Sometimes I post in a thread and only realise there was a reply to it many days after, because I forgot I posted in it. It would also be useful to check that 'new' list if you've only got a short time.