I've never understood the word 'testimonials' within a project. I think everybody knows about writing reviews.
I'd like to see a better way of sorting and locating projects. Something like the two-dimensional selection system used on many sites including YouTube (http://www.youtube.com/videos)
First you select the attribute that you want to sort on - rating, downloads, reviews, activity and so on.
Second you select ...
please review the current category names and regroup the projects under more populair category names.
I have added a map I recently made for categorizing applications...