For many people, a subject that was not included in Aleister's thread has been deemed the ultimate problem. That problem: The patch. For anyone who has downloaded EITHER patches 1.01 or 1.02, the likelihood that this is the freeze culprit is astounding. Just see this example, one among many: http://www.gamespot.com/ps3/rpg/falloutnewvegas/show_msgs.php?topic_id=m-1-56922511&pid=959558
Anyways, to fix the patch one unfortunately needs to delete the game utility on Fallout: NV. I know, it svcks, but if you want to play the game, that is the sacrifice to be made. I wish we wouldn't have to go through this, and Bethesda had just done things correctly, but, alas, such is life. Hope this helps, and any other helpful info should be added to the thread.

why were people still getting freezes pre-patch then? have you owned the game since it came out?

yes, I have. This is, admittedly, only a KNOWN fix for those who experience freezes upon attempting to enter VATS. I do not credit it as a cure-all silver bullet, i just hope that it might help some. It's not like i aim to compete wit you, I am just humbly adding a helpful suggestion that I failed to notice elsewhere.

I'm not saying you were trying to "compete" with me, lol. I know the patch probably caused more problems than it fixed, but freezing issues were still abundant pre-patch, and like you said this is for VATS issues. the title just mislead me, and you hadn't mentioned anything about VATS in your original post.