It is expected that Apple will refresh their line of Macbook Air laptops only after the release of OS X Lion.
The update is expected to include Intel’s ultra-low Sandy Bridge processors & Thunderbolt ports and it is rumored that if Apple wanted to, they could hit the refresh button any day now. However, they seem to be holding out until Lion hits the streets before releasing updated Macbook Airs that will come with OS X Lion installed.
Apple is also said to be holding back on Thunderbolt focused Mac Mini & Cinema Display refreshes until Lion is released.
OS X Lion is arriving sometime in July at a cost of $29.99 but no definitive date has been announced as of yet.