An update( http://us.playstation.com/support/systemupdates/ps3/index.htm) was released today for the ps3.
I have been experiencing the lag/freeze problem, but after instaling the update it's gotten much better.

I have played about 23 hours and have a save file size of 6mb.
This might help you too.


Btw, I just joined and this is my first post.

I still had the issues after updating :/ If it was better, it wasn't by much at all...

I hate to say this, but you've probably got the placebo effect going on. I changed my PS3 video settings and thought that the problem had been resolved, but it came black. Play for a few hours and see what happens.