Get your MacBook Airs updated with the latest firmware update from Apple.
According to Apple, the MacBook Air EFI Firmware Update 2.1 includes:
fixes that enhance the stability of Lion Recovery from an Internet connection, and resolve issues with Apple Thunderbolt Display compatibility and Thunderbolt Target Disk Mode performance on MacBook Air (mid 2011) models.
This update will update your Boot ROM to MBA41.88Z.0077.B08.1109011050
This is great because Thunderbolt hardware is starting to arrive on the market.