Agreed, it's a bit of a bummer having the extra size of the lens adapter always on the camera, but most of the shooting I do, I will want my polarizer on anyways, so I guess it's no big deal for me....
I just got my S2, and have noticed a delay in focus a few times already. A bit frustrating honestly, because the Nikon I had been using up until now would have had no problems in the same situation....