Here's another article with strong believe that Firefox OS is better than Android OS
The main points are similar to another article I linked in previous post: cheap and web-based HTML 5 which sits on top of Android kernals.
Personally, I still don't see the budget level phone would make a big impact. In my opinion, those who demand the open-source everything (possible) usually demand the best of the best and the latest of the latest, at all cost.
It is well known that Google is one of the very few well loved companies by those open-source groups, however, some still "hate" Google. Now, Mozilla Firefox OS is virtually a package on top of Google's Android. It still has Google's blood by the end of the day. Further, for those who can not live without the latest version, latest patches of whatsoever, Firefox OS update is ought to be behind Google's Android if there's some update in Android kernal.
UserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:13.0) Gecko/20100101 Firefox/13.0.1 AlexaToolbar/alxf-2.15