Please see the following post where we acknowledge the performance issues with the game and that this is currently one of our highest priority items to work on: http://www.swtor.com/community/showthread.php?p=5239140
In addition to the previously posted steps another thing that can improve performance in the interim period for nvidia users is to ensure that Ambient Occlusion is turned off. We have seen reports that this change can have a big performance impact.
We ask for your patience until performance is returned to pre-1.4 levels.
Well I have done all that you suggested, and my Ambient Occlusion was already turned off. It hasnt helped. Additionally, the gamma can no longer be adjusted in game to brighten the screen to what it was before. (very dark now). I'm glad you all have acknowledged the problem. In the "interim", however, I wont be playing because its just too annoying and frustrating. I give you 30 days more, then thats enough. I will simply seek my gaming elsewhere.