This one literally took me days to figure out: http://stackoverflow.com/questions/11836468/fragmentpager-not-updating-views
The problem was that Google had inconsistency (which is expected) between its Fragment classes and Support Library's Fragment classes that some of the methods are not implemented and also not well documented. In this case, destroyItem() was not properly implemented, so that it doesn't matter what other methods you override. Ended up almost reimplementing the whole class. :)
Just want to complain a bit here because it really took a good amount of time. Hopefully the support library will get better soon.