Apple released MacBook Air Flash Storage Firmware Update 1.1 on Thursday, an update that fixes a data loss problem with mid 2012 MacBook air models.
MacBook Air (13-inch, Mid 2012)
The patch notes for the release:
This firmware update is recommended for MacBook Air (mid 2012) models.
Apple has discovered that a small percentage of flash storage drives in these MacBook Air models have an issue that may result in data loss. This update tests your drive and, in the majority of cases, installs new firmware to resolve the issue. If your drive cannot be updated, Apple will replace it, free of charge
The update is for OS X Lion and Mountain Lion, the two versions of OS X that run on this MacBook Air model (Mavericks is expected to be released on October 22nd).
If you have this MacBook Air model, the firmware update should be available in the Mac App Store. It's also available as a standalone updater as a 2.21MB download.