C.J.
My husband and I worked on opposite ends of metroplex. So we preferred to have them close to our house, pediatrician, etc. that way either one of us could be on parenting duty :) meaning if the boys were ill, it was my husband's "turn" he didn't have excuse that he had to drive all the way to X and pick them up. It also kept them out of the car for long periods of time in the AM and PM.
Of course, I got lucky with the last two child care centers and they were employer owned/ran and near my house!!