I am a photographer and I'm looking for a laptop to edit pictures on the go and to meet with and show clients. I already have a 24" Imac that I do the main share of editing on. I currently use Lightroom2 and might purchase photoshop in the future. Im trying to decide which macbook pro to go with. I have narrowed it down to the 15" mbp but I'm debating whether or not to go with the 2.66 ghz with 320gb and the 9600M GT with 256MB graphics card or the 2.53ghz with a 250 gb and the NVIDIA GeForce 9400M graphics card. My question is, will the better graphics card make a noticeable difference for the extra $300? Any help would be greatly appreciated. 