So, I had to exchange my 13.3 MBA and got its replacement last week. Before I sent the first one back I wiped the SSD and the Disk Utility showed that it's capacity was ~128 GB. Well I got the replacement MBA and this one is reading that my capacity is ~120 GB. To be clear, this is not my current capacity of the drive...it's the total capacity. Can someone explain to me why I don't have the full 128 GB that Apple advertises? I remember there was an early thread about this topic that was posted about the time that the new MBAs were first released, but 3 MRGoogle attempts didn't get me the thread I was looking for. Any input would be appreciated!