Its a Leica 36 to 432mm lens. As you may have guessed I'm using one of the Panasonic Lumix FZ series, however i never had to fully zoom all the way to 432mm to take those shots.
user111: If you're looking for a digital camera upgrade from an SLR, the FZ20 is the camera for you. It feels and works like any normal SLR would plus the 12X zoom makes it perfect for long distance street potraiture/ voyeuring :)