cogadh: Movie theaters don't play DVDs on the large screen, they actually play film. Some fully digital theaters are probably using digital format media, but most, even IMAX theaters, still use film projectors, so I don't really see how the roll of film that is delivered to a theater could be used for a bootleg before the film is shown in the theater. Any of the bootlegs I have seen were actually produced via "camming" (setting up a video camera in the theater to record the film as it is projected on the screen) so those don't actually ruin the ending before the public has a chance to see it, they just hurt future DVD sales.
If someone were to get a hold of a copy of the film that would normally be delivered to a theater (not easy to do at all), using it to make a direct copy of the movie requires a very expensive and hard to obtain piece of equipment called a telecine machine. Additionally, film copies of movies are encoded with a "fingerprint" of sorts that identifies the specific copy of the film, making unbelievably easy to determine the source of the original film used to make the pirated copies. Producing pirated copies via that method is a great way to get yourself caught.

michaelleung: I thought they were in HD... or am I missing something? In theory, 35mm has more pixels (and therefore higher resolution) than HD digital stuff, so I guess the cinema would have better quality than your Blu-ray player! But what if the film was produced with RED cameras in digital 1080p? They can't possibly use film...
Those "high definition" movies use 70mm film, not 35mm film. They don't record the images on film (they are recorded digitally), but when they are projected they still use film.
TheCheese33: By the way, could anyone recommend me a graphic novel I might like if I enjoyed Watchmen? Tried reading Sin City and 300, but couldn't stay on those because they were almost exactly like their respective movies. It probably would've been smarter to read those first, but oh well. Also, is From Hell any good? I love stories about serial killers, and a graphic novel focusing on one of the most famous, Jack the Ripper, might be an exciting read. Also, it would be interesting to read Alan Moore's other works.
From Hell is great and sufficiently different from the movie that you should still enjoy it. If you like serial killer stories like Jack the Ripper, then you might enjoy Batman: Gotham By Gaslight. Its one of DC's "Elseworlds" line of comics where they take major characters and place in different times, places and situations. The Gotham By Gaslight plot is basically a "What if Batman was born in the 19th century and Jack the Ripper came to Gotham?" story. Another Elseworlds story that is very good is Superman: Red Son, where instead of landing in a Kansas cornfield, the infant Kal-El landed in Soviet Russia and was raised as a hero of the U.S.S.R. There are several different stories in the Elseworlds line, most of them are really good and don't really require any previous detailed knowledge of the characters (what if Bruce Wayne was picked to be Green Lantern, what if Superman was found and raised by Thomas and Martha Wayne instead of the Kents, what if Batman were a priest in a theocratic modern society, what if Superman arrived on Earth during the middle ages, etc.).
If you are interested in Alan Moore, you might like V for Vendetta or the League of Extraordinary Gentlemen. Again, if you have seen the movies, the books are sufficiently different that you should still enjoy them. For some of Moore's mainstream work, I can't say enough about Batman: The Killing Joke. It has what is possibly the most evil interpretation of the Joker ever put in print.
Other books that you really should check out are Batman: The Dark Knight Returns (best Superman/Batman fight ever), Neil Gaiman's work on Sandman (just... trippy), Kingdom Come (beautiful painted artwork by Alex Ross). On the Marvel side of things, I'm an X-Fan primarily, so I have to recommend the X-Men stories Asgardian Wars, Days of Future Past, The Dark Phoenix Saga and the Age of Apocalypse. Additionally, I have a particular fondness for the Marvel 1602 storyline, which is like Marvel's version of an Elseworlds story where they placed the entire Marvel universe in the early 1600's instead of the modern age.