Well I can actually help someone..
The Airport in JAX is about 25 minutes from downtown. There really is not much around the airport. There is a Denny's and a new Ruby Tuesday. I would suggest renting a car and getting a hotel in the downtown area. Omni, Adams Mark and a few others.
I will be in SFO this weekend and will be staying at the Grosevenor Suites near Nob Hill. Is this a descent place? for 99/night I could not pass it up.