If Bing: (1) gets another 4% from Google over the next year due to IE defaults and advertising; (2) gets another 2-4% from the FB deal; (3) signs a deal with

If Bing: (1) gets another 4% from Google over the next year due to IE defaults and advertising; (2) gets another 2-4% from the FB deal; (3) signs a deal with Apple to become default on iOS (2/3 of mobile = 5%+) and desktop Safari (4%+). That could potentially put them around the same market share as Google. None of those propositions are crazy either.