The "No Russian" scene in Modern Warfare 2 has players working undercover with a terrorist organization as they open fire on the crowd at a Russian airport. In most versions of the game this scene is skippable, but it doesn't appear at all in the Russian PC version of the game. Speaking to Eurogamer, an Activision representative explains why.
"Other countries have formal ratings boards that we regularly work with. However, Russia does not have a formal ratings entity. As a result, we chose to block the scene after seeking the advice of local counsel,"
Probably a wise move on Activision's part. In the same statement, the company also addressed rumors that the console versions of Modern Warfare 2 were being pulled from Russian shelves in order to remove the scene, explaining that no console versions of the game have been released in the country.
Activision chose to censor Russian MW2 [Eurogamer]