Have to agree with that for now. Going forward not sure what happens when someone does a factory reset, but going forward I don't think there's going to be as much curiosity about sales.
The problem with Chen's 3 Million number is he said it was based on that $315 ASP. If the next device is a mid-range phone at a mid-range price, the ASP will drop and thus sales will have to increase. Or he'll need to keep the ASP high... which he might can do in the enterprise market.
The way Chen talked it sounded like he was moving forward with plans for changing the way they distribute phones (direct sales). So have to assume the only reason to do that is if he plans to make at least one more new Android device.