Well, as much as I hate Android, these kinds of stats say nothing. There will be developers who do better on Apple, there will be developers doing better on Android. This is just anecdotal evidence.
On the other hand, this article:
Piper Jaffray: Android app revenue is 7% of iPhone's - Apple 2.0 - Fortune Tech
Is much more solid - it says, that while Android downloads are higher, the actual money spent on that platform is far less than what is being spent on iOS.
In other words - Android users don't like to spend money.