If you have a mobility card, especially in iBooks do not download ati displays 4.4.1. It will ruin the OEM opengl settings. It has made vendetta unplayable for me! Apparently it has been fixed but 4.4.2 wont be out for a little while. If you do manage to mess it up b4 you read this, go here and reinstall 4.4

http://www2.ati.com/drivers/macosx-radeon-displays-4-4.dmg

4.4.2 is out NOW!! See Macupdate.com