The Vision Mobile Developer Economics report has an interesting chart showing fragmentation of the various platforms. That is, the number of versions of an app that have to be developed to cater for different versions of a given OS.
This concurs with my previous observation that problems of Android Fragmentation have been exaggerated. However, I suppose it depends on your reference point. As the chart shows, if you are only coming from iOS then it will seem more fragmented. If you previously worked on Java ME, Symbian, BlackBerry or Windows Mobile then Android Fragmentation won’t seem that bad.