For the upteenth million time someone has asked a question like this the answer is always the same: NO ONE KNOWS!
Apple likes to be a secretive company, and whether you like that or hate it isn't going to make anyone have any more concrete information. So no one knows for sure until there's an official announcement. Until then it's just a rumor, and rumors regarding Apple products tend to be wrong as often as they're right. I clearly remember people being convinced that the iPad would be called the iSlate, and released months before it actually was. Then there were rumors about features that would be in the iPad 2 which were nowhere near accurate. Some of them were more or less spot on, but there's no real way to discern between the two until after the fact.
And you don't buy a MBAir because you want processing speed, you buy an Air because you want the portability and long battery life. If you're looking to get an Air because it's fast, look elsewhere. The SSD lets it boot rather quickly, but when you get down to it, it's considerably slower than it's MacBook and MacBook Pro siblings. Even if Apple puts a sandy bridge CPU in an Air refresh, it's going to be a low end dual core model because, again, the Air is designed for portability and battery life, not performance. You want performance, get a MacBook Pro.
Okay so according to http://news.cnet.com/8301-13924_3-20031434-64.html?tag=mncol;txt and many other insinuations around the web, the Macbook Airs will get a processor update coming June to the new Intel processors.
Are these rumors usually accurate? Will this update most likely happen? I am about to purchase a MBA, but hearing about the processor update would make waiting worth it as the i-Series from Intel is faster than the Core Duos.
Would the update be for both 11 and 13 inch models? I read from a certain website that only the 13 inch model will see the new chip. May this be true? I want to buy the 11 inch MBA, and it would be a shame if only the 13" will get the Sandy Bridge.
Any clarification on this? Thanks!

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