As Wiki notes:
Watchmen remains the only graphic novel to win a Hugo Award, and is also the only graphic novel to appear on Time's 2005 list of "the 100 best English-language novels (Go to full Wiki entry)
Moore also wrote V for Vendetta - which was turned into a pretty good film with Hugo Weaving and Natalie Portman.
The Watchmen movie looks fantastic with a great cast featuring Patrick Wilson, Billy Crudup, Matthew Goode & Jeffrey Dean Morgan.
Is that a hot group of superheroes or what?
So, so excited.