I just thought it was interesting that this article implies that the cop is
a robot. In other interviews with J.J. I've seen him state that the airbike cop was a human being.
I agree that the pipe sequence was marvelously executed, and I suppose I figured that the pipe sequence had to be CGI--there's just no way Anheuser-Busch would allow Simon Pegg to swim around in their brewery tubes.
Of course that would explain a great deal about the taste of Budweiser.