no, you will be able to overclock the snot out of that 6600. you have a nice config picked out there. good mobo, great video card, sufficient power, etc. pick yourself out a nice CPU cooler and start tinkering!
As far as the photoshop is concerned, have you opened the NVIDIA main page? You won't need 8GB of ram if you have a gtx 260, it will run smoother than and cpu based version on any system. and as far as the bottle necking is concerned, neither of those 2 games should eat up all of you CPU.
Thank you for your thoughts and for pointing our the nVidia page.
I just wanted to be prepared because Premiere gobbles up all 4GB of RAM on my current (albiet ancient) system when editing hi-def content. I don't mind spending $60 more for 4GB more RAM but I guess I can always buy more later if needed.
Well if your editing High Def video, it might come in handy, but don't forget, that if you want to use more than 4 gigs of ram, you need a bit operating system, and probably a 64 bit version of Premier.