i'm getting the 200gb now because none of the stores in oregon will put the 250gb in the base model. (i'm driving down from washington, trying to avoid tax so i can't order it online). I think that 200 would be enough but if down the road i realize that i want a bigger hard drive, is that easy to replace? Does it void the apple care warrenty? What's the best way to get all of the information from the old hard drive to the new one? (sorry for my noobness but idk how i would get the computer started and running since the new hard drive wouldn't have anything on it). Any help would be greatly appreciated! Thanks a lot!