There are advantages and disadvantages to the one vs. many options on both sides. IOS will lose share, but IPhone will continue to be the best selling handset because of it's huge installed base. Apple is not dumb - they know as the market becomes commoditized that they'll make more money off premium positioning leveraging the brand/image by bundling the OS and hardware. They would weaken the brand/value of both by splitting that union, nor do they appear to have any interest in the added complexity of rolling out additional options which could negatively impact quality. I think if Nokia and WinMo do partner there will end-up being 3 major players in this market, possibly 4 if RIM ever gets its act together. I also expect a major assault from both IOS and Android on the enterprise market this year. The outlook for RIM is dire.