Hi guys, so i went to the store yesterday and bought the rMBP 13" i5/2.4ghz/256ssd/8GB ram. I've been checking the Acitivity Monitor quite often and it says that I'm using around 2.5gb of memory even though I'm not doing anything! and when safari is open with around 5 tabs its ~3.5gb of memory. Its my first mac so i don't know if its normal. On my old sony vaio i never went over 3GB even with 20 tabs open using chrome. I want to install parallels so that i can run win7 too now I'm thinking about returning this model and order the 16GB Ram version. money is tight but if i make such an big investment might as well kinda future proof it. I'm planning on majoring in computer science and want to keep this mac for ~4years so what do you guys think?