I received my MBA 2012 only two days ago, and last night I found there is a small gap btween the bottom case and upper panel on the left hand side near the trackpad. I suppose it may be the defective battery swelling making the case warped. It is my first Macbook product, I'm really disappointed. Im just wondering is it very common for Macbook? Should I ask for a new MBA replacement or just the battery? Coz my one is customized with 8G ram, and it took me almost one week to get after I placed my order. Am I lucky or unlucky with this experience?