I dont think you will need it, I dont have the specs in front of me, but if your getting a 13 inch MBP, you wont need 8 GB thats for sure and I would recommend 2. I have an Imac, 24" and I run massive video editing stuff, photoshop and multiple web windows with 2GB ram with no slow down at all.
Someone once told me 2 GB on a Mac is equivalent to 4 GB on a PC. I hhaven'texperienced anything to make me think or feel otherwise.

I am just about to pick one up. I will likely get a 4GB 250GB HDD 13' for $1500 as it's within my price range and I can do the stuff I want to do on it
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