BMW's semi-auto tranny is SMG.

It's a clutch-type transmission with a robot doing the clutchwork for you. (Forgive me for any errors, this is from dim memory).

DSG is Volkswagen-Audi's take. It's a robotic tranny that uses two clutches, with gears on two separate assemblies. You're in second gear, for example, and the other assembly, which has first and third, is free-wheeling. Select third and the other assembly engages while the first disengages. Theoretically, there is no limit to how fast this can shift. It's almost as efficient as a manual, it'll hold more power than Honda's CVTs, and it's still lighter than the heavier duty mechanical CVTs and torque-converter based stuff.