I agree with you 100% Joker454. XCode is hard to get into in my experience too, though, having said that, XCode 4 (which only recently came out), is a big step forwards in user-friendliness. But it's still quite difficult, just from the alien notation style that has been used in most documentation alone, but also with all the reference counting and different UI design paradigms.
Of course, fair's fair, those different UI paradigms are good paradigms, but that doesn't make them easy to get into. I've been immersing myself into WPF over the last few weeks, and although it's not always easy or behaving quite like I want, I've been making huge strides at much better speed then I ever managed to do in XCode. It's obviously partly a matter of what you're used to, as I know patsu had no problems getting into it, but I think he was always familiar with the Mac environment anyway, and that was a strategy I decided to take as well - just code some Mac OS/X stuff first because easier to experiment with, and then go back from there.
I've installed the Windows Phone SDK on my laptop, and it seems very friendly to use as well. When I'm happy with my WPF progress, I'll definitely go back to it to see how closely the two are linked in terms of layouting - I expect pretty closely - and I look forward to making some good steps forward on WPF.
Ideally, I would like to be able to code on all three platforms (Android, iOS, Windows Phone), just to get my understanding of stuff to a higher level, much like I've always felt studying several foreign languages have offered a better understanding of language on a meta-level, but obviously it's much more interesting to focus on what you have yourself. I'm glad they're all around right now though, and I hope they keep competing for a long time, just like I'm happy that Sony, Microsoft and Nintendo are all out there in the console space.
What helps a lot as well, is that WPF matches the way I've been designing UI for Windows Forms 2.0 for a long time now. Sometimes I think I'm completely wasting my talent at the small-time business development work I do, because so many technologies I've developed when they were avant-garde turned out to become commonplace and integrated into some big framework or other 5 years later, but obviously they become part of these frameworks precisely because a lot of people agree that's the sensible thing to do.
Anyway, definitely a good idea to focus on the new platform right now, as I agree that will give you much better exposure, and while there's no harm in having some of your stuff ported obviously to test the reception on different platforms, I think it's very good to also have some exclusive content, even on purpose.