I had some problems with my mba and I went to the apple store to get an exchange, the manager clearly saw the white line problems on the mba and he gave the ok for an exchange but I walked out with a 15" mbp 2.5Ghz model and couldnt be happier!
17" was too big especially the resolution (for me though so its subjective) and I'm a young guy but I tend to squint alot and the mba was an awesome machine but the fan noise once in a while annoyed me + while I waited for the genius I saw 3 other people happily using their mb and I thought to myself man the mba is pretty expensive.. so I walked out with a 15" and wont ever look back!

17" was too big especially the resolution (for me though so its subjective) and I'm a young guy but I tend to squint alot and the mba was an awesome machine but the fan noise once in a while annoyed me + while I waited for the genius I saw 3 other people happily using their mb and I thought to myself man the mba is pretty expensive.. so I walked out with a 15" and wont ever look back!