I've decided on the 15 inch. Is it worth going from 2.0 ghz to 2.2 or even 2.3? Will I noticed a major difference? I'm leaning towards getting the 8GB of memory. Thoughts? On my hard drive ... I'm leaning towards the 500 GB @7200 rpm over the 750 GB because of the speed. I have an external hard drive I use now. My MacBook Pro now only has around 160 GB, that's why I'm thinking the 500 GB with faster speed is fine. What differences in speed will I notice? Thoughts? Thanks for the help.