I used it back in the day and liked it. Other than being used to Basecamp, I don't really see why anybody would choose it over Asana in 2012 though. Given the choice between a free Basecamp and Asana it would still be an easy decision.
I get more done in new Basecamp than in Asana. Basecamp is better designed and better engineered.
I found Asana quite frustrating to use, and am happy using Basecamp.