I've heard absolutely nothing about any plans to build additional swap stations, but I used the existing battery swap station at Harris Ranch four times last year and the manager of the swap station (Mark Brooks) confirmed today that we should be able to use the swap station again for our upcoming road trip in June. One of the battery swaps we did last year was on December 19th and about five minutes after our swap was done, another Model S arrived for a battery swap. So we're not the only ones using it. Once Tesla finishes building superchargers along the lengths of interstate 80 and interstate 10, I hope they build some more battery swap stations. But I'd much rather see the swap stations located in urban areas (perhaps next to Tesla service centers) than at places like Harris Ranch. My main use of the swap station at the moment is to borrow a newer battery with a bit more capacity than the one in my car for road trips that venture far from the nearest supercharger. Stopping by the local service center for five minutes the day before the trip would be more convenient than scheduling the trip so that it hits Harris ranch during the hours when the swap station is open. Urban battery swap stations would also be fantastic for people that live in apartments or condos without any convenient way to charge their cars overnight.