Can you point to any reference that mentions the profitablity in established markets? All the articles I see say that unit economics remain unprofitable in all cases.
From sources familiar with Uber finances, I have heard they are indeed profitable in many established markets, but in all of these markets the only reason they are profitable is high-margin products like Uber Black. If governments start requiring a certain amount of Uber's business to be carpooling to reduce traffic etc., Uber will not be profitable anywhere.