I recommend going early. Because by about 1:30 or so, Nimitz Drive is backed up. All the scary health stories have only succeeded in creating more demand and making Abel Gonzales a folk hero.
Other State Fair notes: this year's car show is kinda depressing. The Centennial Building with the foreign manufacturers has fewer cars and fewer lookers than I ever remember. The Auto Building, with Chrysler, GM and Ford, is crowded but lacks any big attraction. Clearly, what's needed here is more spinning stages. Maybe a few women in evening gowns. I know big-time glamour and showmanship might be impossible post-bailout but if I ran Ford I would go for serious glitz. After all, slightly more women than men attend the State Fair car show. Why not go red-carpet with it? Thank goodness for the outdoor Truck Zone.
Whatever you do, though, you must visit the livestock barns. Personal fave: Santa Gertrudis. They're big ol' things.