I guess I missed this when it first came around....
With continued supply problems, its hard for me to see it getting to 10mm. I think without those constraints, X/S might get to 11 or 12 million. But, they can't sell units that don't exist. As for making a prediction, I don't really know how to do that with the current unknowns about supply. I'll pull something out my ass though and say 9 million units.