Picket Shopping Center is across the street with the Total Wine and Chuckie Cheese.
The shopping center where the Giant was is Turnpike Shopping Center. There is already a thread for that at
http://www.fairfaxunderground.com/forum/read/2/268702.html
it has some recent posts about what stores are coming.
as to why the owner can't get tennants, if you haven't noticed it hasn't been the best economic times to open a business. They both seem to be owned by combined properties so it seems unlikely they are charging substantially more rent in Turnpike