I also see FirefoxOS as Mozilla's long-shot hedge against the spectre of walled gardens. With first iOS and then WinRT disallowing third-party browsers, a world dominated by locked-down platforms would be a death sentence for Firefox.
I always wondered why no one tried lawsuit on that topic in Europe for iOS devices? It is arguably worse than the IE situation (you used IE just once to get a real browser), but right now Safari is only game in town for no technical reason and everyone is cool with that. No addons, no adblock ...
