Could Count Dooku as a Sith be a surprise?
Wow, um, okay.
>>>Will anyone watching Ep II really be surprised when Dooku is revealed as a Sith, or care?
I think GL thought it would be a bigger deal than it was, and the "mystery" of the assassination effort. He doesn't explain Dooku much at all so why are we concerned with him until he first appears with the Separatists?
Also, there are some external factors that make movie surprises (in blockbusters at least) difficult these days, including pictures of Chris Lee around the release, and he wasn't a good guy so he's probably a bad guy.