Not sure if this would be possible, but just a suggestion.
Right, when you search for something you can search by a word/phrase and user, or just a word/phrase. What you can't do however, is search solely by username. This would be a handy feature, such as if I wanted to search for all topics in say...the Zelda Graphic Arts forum by TaKaM, or all pssts in the Programming section by Goodnight. I think it'd be a good feature for the new forum, maybe if you could let the 'Search for' box support wildcards.