I was able to update my rMBP. When I tried for my late MBA 2010 app store said there is no update available.
When I download the update file from http://support.apple.com/kb/DL1571 and tried installing it, I got another error, "OS X update cannot be installed on this disk. This volume does not meet the requirements for this update."
What can I do about this?

When I download the update file from http://support.apple.com/kb/DL1571 and tried installing it, I got another error, "OS X update cannot be installed on this disk. This volume does not meet the requirements for this update."
What can I do about this?