Back when Steve Jobs was CEO of NeXT, and it wasn’t clear that the company was going to survive, open source developers cloned the company’s crown jewel, OpenStep, with GNUStep. Then OpenStep morphed into Mac OS X, and GNUStep was largely forgotten.
But the great thing with open source software is that nothing gets completely lost. Sony’s working on a software platform using GNUStep on top of Linux.
There are good technical reasons to use GNUStep, and for a long time the biggest reason not to was that having to to learn an obscure new language (Objective-C) scared away a lot of developers. My guess is that the fact that Apple has convinced so many programmers to use Objective-C for iPods made an impression on Sony. That and the fact that Apple has shown that Objective-C works well on low-power devices.
This makes me suspect that Sony has decided that if they can get cross-compatibility with only one platform, it’s Apple’s.