I have 2008 15" MBP and upgraded to 2011 13" MBA two weeks ago because of it's potability and i need to take it to school everyday. before i bought MBA i told myself that after i bought my MBA i'll sell the 15" MBP and get some money back but now i'm having second thoughts. I really like the 15" MBP screen. I been using 13" MBA since i got it and it's fine for me tho. So my question is should i keep the MBP or should i sell it? For those who upgraded from MBP to MBA do you guys still keep both laptops? Thanks.