I agree that this is a major failing of the mac app store as it currently stands. Given that for updates there is a high likelihood that the previous version i

I agree that this is a major failing of the mac app store as it currently stands. Given that for updates there is a high likelihood that the previous version is on-disk, sending some type of diff would be very beneficial to end users. Even if it is a diff for only the previous to the current version, with a full download required outside that window.