well since you guys helped me build quite the desktop thought i'd ask on RS which macbook to buy. don't know anything at all about apple products other then having an ipod and an iphone and before this turns into a get windows laptop instead and two sides arguing which is better

I just want to try it out so it doesn't really matter which is better. Most of the time I will be using my desktop with windows7 on it. anyways is there anything new around the corner I should wait for? I know there is always something but something "big"? Also any suggestions on which one to get? planning on taking it to class etc. I have a sony vaio right now but the battery went to hell so thought I'd try out a mac as well. Thinking 15" screen is good?
thanks