I think it is pretty clear now: If now wonder happens, we are stuck with Android 4.2 on our FP1's. I know the Fairphone team is thinking hard about what to do about that. A lot of us have pointed out how sad it is if a phone with perfectly good hardware is out-dated because of missing software updates. I think the problem lies in Mediatek's software service / policy not supporting low volume/low cost chipsets and not opening drivers and documentation so the community could step in and Google abandoning old Android releases pretty fast without even providing securtiy updates.
Apart from that, while Android gets better and better looks and great features each release, Google seems to slowly back of their open source strategy. The core of Android will always be open source, but more and more user applications are left behind - starting with the music player, gallery, camera and email, a lot of the open source apps included in Android are dated.
Now, I have used a Firefox OS phone briefly before my Fairphone arrived and really liked it. On the desktop I switch between OS X on my laptop and Ubuntu Linux on my PC and almost every PC at work. And I also run a Windows 8 for gaming. So you can consider my pretty open minded and i am used to adapt my workflow on different Operating Systems. And i really feel at home with Ubuntu. A few questions aside - which i asked about in the Ubuntu Community - it's a no brainer for me: I would love Ubuntu on my Fairphone. And i am not only talking about the FP2, i also keep thinking about if there should be a community port (best would be if supported by Fairphone) for the FP1 and FP1U. Both hardware is powerful enough.
There are still a lot of open questions, nobody knows yet if Ubuntu on the FP is ever happening. But as i might be biased and as i certainly curious and enthusiastic enough, i might not be a good representation of the typical FP user. You might have completly different thoughts on that and i am very interested to hear them!
PS: Spontaniously, i think the only apps i would miss is Here/OSM for offline navigation, WhatsApp and the DB Navigator for buying train tickets mobile here in Germany.