Apple has won many fans with its Retina Display on the iPhone 4 and 4S, and now on the new iPad as well. But according to one developer, this love could soon be shared with MacBook users as well.

A source with access to the latest Mac OS X 10.8 (Mountain Lion) preview, who spoke to Ars Technica has said that double-sized graphics have popped up in some unexpected places, once again suggesting that Apple may be close to releasing MacBooks with high pixel-density screens.

One of his examples comes from the new Message service, which has replaced the outdated iChat, where some icons are displaying double resolution art. This has happened in the second update to the developer preview of Mountain Lion, and in the image below you can see the "audio chat" icon is a 2x version instead of the standard 1x version.

Retina Display Macs
Some icons are displaying double resolution versions in Mac OS X Mountain Lion

"I would interpret it to mean that Retina [MacBook] is close; perhaps concurrent with the release of OS X 10.8," the source told Ars Technica. Apple has not set a release date for Mountain Lion yet but it is expected to go on sale around the time of Apple's Worldwide Developer Conference (WWDC) which takes place every year in San Francisco in June.

The question is not whether the technology is out there to be able to create these types of display (it is), but whether Apple wants to incorporate the Retina Display in its MacBooks or retain it for the iPhone and iPad only. There is also a question of cost, though with this technology coming down in price recently, this is probably not a major consideration for Apple.

Of course we would like to see Retina Display MacBook Airs or MacBook Pros and with the last refresh of both models not very exciting, we expect to see something big from Apple in the summer. Along with Retina Display screens, we also expect the new laptops to come with Intel's latest chips, codenamed Ivy Bridge.

Ivy Bridge, which has faced some delays recently, promises to improve on the general performance of the current Sandy Bridge chips as well as improving power efficiency and significantly improving the integrated graphical performance.

MacBooks and in particular the Air model have faced stiff competition from the new wave of Ultrabooks though none has manage to combine the sleek lines, great screen and powerful performance of the Air. However, with Ultrabooks like the HP Folio 13 coming close and costing a lot less, Apple will need to improve just to stay ahead of the game.