Be sure to check out David Swindle's review of V for Vendetta.
I saw the movie, but didn't comment on it because I thought I really didn't have much new to say as what had already been written in other reviews. I enjoyed the movie and got the impression that it stayed fairly faithful to the original comic series (they didn't "rape" Moore's work like the adaptation of League of Extraordinary Gentleman did). Yet, I read the original series many years ago and didn't reread it in preparation for the movie (so perhaps my thoughts would have been different if I did).
As far as the "terrorism/freedom fighter" thing goes, forget whether the bad guys in the movie were metaphors for the neocons or for the Thacherites of the 80s (which is what Moore had in mind in his original series) and take the ruling powers at face value. As an earlier review pointed out (I can't remember which one) in the movie, Britain's rulers were like "what if Adolph Hitler had won World War II?" Putting it into that context helps to understand why the hero was so angry and wanted to blow up Parliament.
Swindle makes a good point. As bad as Bush or any Western ruler may be, it would be a Hell of a lot worse if Bid Laden or the Taliban actually ruled us. And the fascists in power in V were that bad. I know that were Bin Laden in charge in the USA, I certainly wouldn't gracefully submit to his administration's authority. As Swindle writes:
There's been plenty of controversy swirling around "Vendetta," most of it idiotic. What's the difference between 9/11 and V's bombings of various London buildings? Or, what's the difference between a terrorist (Bin Laden) and a freedom fighter (V)? Easy: V's acts of terrorism are designed to free an oppressed people. The goal of 9/11 was just the opposite: the promotion of a totalitarian ideology appropriately labeled "Islamofascism."