Comes with the game, installs automatically, not sure if you need it but I wouldn't bother uninstalling it since it's actually not bad and takes up little room. --- PSN: Kanemura ~//~ FFXI: Kanemura (Diabolos) "Always forgive your enemies; nothing annoys them so much." - Oscar Wilde
It's not required to play. It's the software the game uses for surround sound functionality, and the game gives you the option to use Rapture 3D (Software audio) or to use hardware audio if you have a dedicated soundcard in your computer.
If you're using onboard audio, I'd say keep Rapture installed and use it for the game, but if you have a soundcard you can uninstall Rapture and use hardware audio instead. --- PC: http://i305.photobucket.com/albums/nn233/cody4783/cody4783.jpg