New superchargers are being installed, see below link.
2013 Tesla Model S: Supercharged
2013 Tesla Model S: Supercharged
Turned out, they were installing two new superchargers to bring the total to four. One electrician described them as "gen 2" chargers and, in fact, the towers were taller. Also, the electrician told me that if two Teslas charged at the same time, the second one to arrive would do so at a slower rate. When the first one left, the slower rate would continue, unless the owner disconnected and then began charging again.