iPhone users (and "high end" Android users), on the other hand, probably know exactly what they're buying into. These are the users that will determine developer targeting. Two ways I see for Android to decisively win this: either these "low-end" users start to participate in the eco-system, or the rise of low income countries (much of Asia, Africa etc) makes the weight of numbers so far in Android's favour that even with a much lower engagement rate, the money's there. Apple could counter this with "iPhone Nano", I guess, but it would require them to sacrifice a lot of margin.
Outside tip: Samsung are becoming the Apple of Android smartphones, selling the preponderance of the high end handsets. Within 18 months, I suspect we'll see them fork Android to differentiate themselves from the "sell at near cost, make it up on ecosystem" strategy that Google's pursuing now with the Nexus (that reduce Samsung to basically a hardware supplier on razor-thin margins). Either that, or they'll use carrier relationships to ensure these cheap, high-end handsets don't ever really get in front of non-geeky consumers.