A new MacBook Air could be on the cards for a release next month as stock supplies of the existing models of MacBook Air have been significantly reducing a third party sellers. According to AppleInsider, Amazon.com have run out of stock of the 13 inch MacBook Air with 256GB storage, and then 11.6 inch Air is heading that way as well. This observation runs parallel to other Apple resellers such as MacMall who also are seeing low stocks.
Third party sellers of Apple products are often the first to display stock shortages when Apple runs down production existing models of an item in preparation for the release of a new version. Certainly with WWDC set to be held in June, it is likely that Apple will be debuting a new version of the MacBook Air with Intel Haswell processors and upgraded graphics performance.
While recent rumors have suggested that the new MacBook Airs will simply be released with a speed upgrade, there is no indication that there will be any major changes to the new models, such as a redesign or a Retina Display. Indeed, Apple will likely update the Retina Display MacBook Pro line with Haswell processors at the same time.