Apple’s latest MacBook Airs haven’t even been on store shelves a week yet, but already there’s talk that a 15-inch notebook will be joining Apple’s ultraportable notebook family. It’s unclear where the device might actually fit into the company’s notebook line, but according to MacRumors, it’s in the final stages of testing at the Cupertino camp:

Apple is working on a 15″ ultra-thin Mac notebook, MacRumors has learned. We aren’t certain if it will be called a MacBook Air or MacBook Pro, but we do know that it is already in late testing stages at Apple.

Unfortunately there’s very little to get excited about right now, with no mention of technical specifications or specifics, but surely the mere suggestion of a 15-inch MacBook Air is enough to get you reaching for your wallet?

There’s also no indication of when the device might be available, though MacRumors speculates that with revamps issued to the MacBook Pros in February, and to the MacBook Airs just last week, we’re unlikely to see the this 15-inch ultraportable until at least the very end of this year.

Apple’s MacBook Airs have proven to be a huge success since the 11-inch model was introduced in October 2010. With it came solid-state hard drives as standard and a very reasonable price tag which undoubtedly contributed to the death of Apple’s entry-level white plastic MacBook. Those super-speedy SSDs also make them a great deal faster than more expensive machines for every day computing.

My 2010 11-inch MacBook Air boots quicker and is generally a lot snappier than my 2010 MacBook Pro, which was significantly more expensive. It’s no wonder, then, that the MacBook Air has been another huge success for Apple — and making a 15-inch model just seems like a no-brainer.

Are you clinging on to a MacBook Pro purely for its bigger display, and would you be happy to say goodbye to it in favor of a 15-inch MacBook Air?

[via MacRumors]