I think GPL may be getting in the way since Lego probably doesn't want to open its kimono too much as far as the underlying Mindstorm controller goes.
There are, however, funtional Raspberry Pi implementations already in the works or available as this project
Supposedly the new Mindstorms is also planning iOS and other mobile support. Hard to really find much out since most of the Google pages discussing the new EV3 no longer go anywhere (possibly because Lego requested they be taken down?)
Unfortunately, with reduced school budgets and a renewed emphasis on "teaching the basics," the cost of EV3 may be prohibitive for many school systems (24 student starter pack
goes for $4700 USD. A single EV3 core set
is $340 without
software, which shows as being a separate purchase. Couldn't find the pricing on just the software. The only page I did find about that merely provided a form to "request a quote.")
Be interesting to read Lego's license terms for EV3. From what I can see it requires a site
license if a school wants to load it on more than on PC! (Doesn't that imply they offer more than one set of license terms to schools?) I tried to find a copy of the license on their website. No joy I'm afraid.