During their 10-year anniversary retrospective of Grand Theft Auto III, Rockstar responded to fan questions and dispelled some rumors about the game and its development.
Responding to questions about how the September 11th attacks effected the game, Rockstar said that, while changes were made, they were mostly cosmetic: Only one mission, which involved "terrorists", was removed. The largest change was, in fact, to the game's box art, which the company "felt was too raw" directly after the attack.
"About 1% different. We removed only one mission that referenced terrorists and changed a few other cosmetic details – car details, a couple of ped comments, lines of radio dialogue etc – the game came out a very short time later. The biggest change was the US packaging which remixed the previous packaging into what became our signature style – because the previous packaging [which was released as the cover of the game in Europe] was, we felt, too raw after 9/11. All of the more extreme rumours are amusing but impossible to have been achieved in such a short period of time."
They also said that they had no plans to release an unchanged version of the game, since it's so close to the final product.
Rockstar also responded (mostly disproved) a whole slew of other rumors. Here are a few:
-The infamous "Dodo" was not meant to fly.
-The tunnels in Shoreside Veil were not supposed to connect to another island that was cut during development.
-Rockstar did work on a multiplayer component for GTA III, but scrapped it because they didn't think it worked very well.
You can check out the full answers to all of these and a whole bunch of other questions at the full Rockstar retrospective.