Honestly I don't get the 11" IMO. The 13" is perfect for someone who wants a laptop with useable screen real-estate but who doesn't want/need an optical drive and doesn't want to lug around a 5lb laptop. My fiancee loves her 13" MBA and honestly I would have gotten a 13" MBA instead of my 13" MBP but the $999 deal was too good to pass up at Microcenter