"It will take until 2006 for supply to catch up with Downtown demand". That's from San Diego Metropolitan's article on the state of real property in downtown. There's a bit of cheerleading by the author but he does note somethings downtown needs: chuuches and pubs!
There's also a decent guide to housing developments that looks like its kept up-to-date.
I just found another market outlook report from Jan 2005. A must-read if you have interest in downtown real estate.