http://www.amazon.com/gp/product/B0...&pf_rd_t=101&pf_rd_p=470938631&pf_rd_i=507846 Is this a good deal? Also, what differences will I notice? It doesn't do anything to the 2.26ghz processor does it? So, I'll go from 2gb to 4gb of memory, but what exactly does memory do? It's not that my mbp runs slow, I figure why not right? Tips, input, advice much appreciated!