4th Sep 2003
Continuity mistake: When the heros arrive at Dana's building, they're saluted by a crowd. If you pay close attention, you'll see the same extra in two different positions (he's the young - and very "happy" - guy wearing a grey suit and a purple tie). (01:19:30)
4th Sep 2003
Trivia: The first time the heroes use their proton weapons (in the hotel sequence), you can see (using slow-motion) that the rays don't actually come from the weapon, but from their target. The rays were "drawn" during post-production and, apparently, it's easier to start drawing from the target to the weapon. (00:31:46)
4th Sep 2003
Revealing mistake: During the "montage" there is a reversed shot of the guys driving their "ghost-mobile" - you can notice it because the Ghostbusters logo is reversed. (00:39:35)