MacBook Air stock shortage adds weight to WWDC range-refresh rumors

Whispers of a full MacBook refresh at Apple's WWDC 2013 this June look increasingly possible, with stocks of the 13-inch MacBook Air already tightening ahead of what's believed to be an Intel Haswell-based upgrade. Apple was tipped to be updating its notebook line-up to Intel's 4th-gen Core processors by analysts back in April, and now stock checks across US retailers would seemingly confirm that the last of the existing models are being mopped up.

The 13-inch Air is the first to go, it seems; according to AppleInsider's inventory checks, the 256GB version of the ultraportable – with Intel's 1.8GHz processor – is showing extended shipping times in the region of 1-2 months at all the popular resellers bar Best Buy. Though the most expensive off-the-shelf model in the Air range, at $1,399, the 256GB version is a popular one give the absence of user-upgradable storage in the Air.

Beyond Haswell processors, there's controversy over what exactly Apple will do to the MacBook range in terms of updates. One much-discussed possibility is a Retina display, bringing the Air into line with the top-end MacBook Pro notebooks, by introducing a high-resolution screen for smoother graphics.

Industry predictions about Retina technology have been mixed, primarily because of the cost and availability of the panels themselves. Some have argued that using such displays would make the Air range simply too expensive to also serve as Apple's entry-level notebooks, or indeed that it would be unable to meet likely demand since yields of high-res screens are still tighter than the more typical panels.

That's something even analysts who predict Retina will be on the table have conceded, with suggestions that – while WWDC will see the new versions announced – actual supplies won't be available until after the developer event. There could also be a split in the line, with "normal" resolution models kept around to cater for the budget end of the market.

Of course, WWDC is also expected to see new details on the next version of Mac OS, OS X 10.9, shared. That updated platform is believed to further narrow the gap between desktop and mobile functionality, borrowing features and UI elements from iOS on the iPad.