I was looking on the Apple website researching the prices for the MBP's and I noticed that the lowest priced 15" model is 200$ cheaper than the middle 15" model(which makes sense) but when you upgrade the hard-drive to the 500gb 5400rpm for 100$ the models seem to be identical. Which means, any one who buys the middle model is spending 100 extra dollars... Unless there is something in that middle model that is not listed that makes it 100$ more. I was wondering if any one knew what this secret 100$ upgrade is, or if Apple is trying to pull a fast one on us. Thanks in advance for the response.