I know the HHKB Pro 2 Type-S just got released last month. It's a more silent version of the HHKB Pro 2. It looks like it's a matter of preference: whether you like the sound or not. I, for one, don't mind the noise, but still want to try out the newer one rather than the regular HHKB.
Does anyone know when we can see the Type-S in North America?