They're defining their own ABI (see pages 28-30 of the presentation). There's no reason why it should have to match 1:1 to native ABI. The next issue (aside from finishing up that work) seems to be ...
Parent article: Free Software: the road to a Universal bundle, a powerful app store, and world domination (Free Software Magazine) They're defining their own ABI (see pages 28-30 of the presentation).