Sure, at a higher level they compete with Samsung in this large "OS pond". There are levels of granularity that you're discounting, though. There's a non-trivial portion of the market that is determined to buy a Windows phone (ie. they enjoy the entire Windows experience as someone buying completely into the Apple experience would). Nokia wants to be top of mind, top of market for these individuals. Until there's data showing that there is indeed a heavy rate of attrition from potential Windows buyers to actual Android/iOS purchasers, it's fair to say that Nokia made a good play, especially since their own OS wasn't going anywhere. Also, Windows 8 and the Surface Tablet only came out last year. Obviously we'll see in the earnings reports how Nokia is faring with these new devices/software, but I'll bet that Nokia is going to be in a better position than it would be if it still had Symbian or Android (would've probably been overshadowed by GS III / IV and HTC One).