Re: Was I the only one shocked during the big reveal?
1. Dent's impending transformation is well known to even the most casual of geeks. But his role beyond that (and the shocking fact of his death) was completely unknown.
2. Everybody had a hunch that Rachel would die but the way Nolan kills her off so abruptly definitely shocked people.
3. One may have known subconsciously that Gordon is alive but the transport chase scene does a masterful job of letting you divert your attention thoroughly from Gordon (ironic since he was there the whole time).
It's the execution of those potentially predictable plot points that made The Dark Knight seem fresher than it really was.