It doesn't make sense. If you want BB10 but one carrier doesn't have it you go get it with another carrier. Why switch OS if you want BB10 anyway?
If I go to a restaurant and want a steak but they don't have steak it would make sense for me to get steak somewhere else. Not head somewhere else and order fish.
Also, most people that use blackberry have it for the enterprise server and security. So why switch to iOS that IT departments say is worst for company security (that is taken from the latest issue of InformationWeek Magazine, it was their headline issue)?
US Cellular missed an opportunity to be the ONLY US CARRIER to carry Blackberry 10 and release it first. Since reviews are generally good I will wait and see if USC decides to carry it. I see Sprint will carry the Q10 so could go there. Thats only other carrier with good signal here. (Except Verizon which I dont care for)