Macotakara is reporting that Apple is testing a MacBook Air with the custom, in-house Apple A5 chip. This would be the first time that Apple has actively started testing its hardware and software on an ARM architecture. The A5 chip is currently only found in the iPad 2, though it is rumored to be included in the next version of the iPhone and iPod touch.
The report says nothing about whether or not the software being run is OS X 10.7 “Lion,” which is supposedly nearing completion. It would be quite the announcement if Apple were to show of Lion running on the ARM architecture at WWDC 2011, and then shipped a new MacBook Air taking advantage of the software soon after.
This report goes in stark contrast to one that Digitimes ran a while back, as they claimed that Apple was busy implementing newer low-power Sandybridge-based chips and Thunderbolt in the next generation MacBook Air.
As MacRumors points out, Macotakara has a decent track record with Apple leaks:
The Japanese blog has had some accurate information in the past, being the first to describe some of the new physical characteristics of the iPad 2. It is certainly plausible that Apple might be testing such combinations in their labs, though its unclear if/when Apple might actually decide to introduce such a machine.