[General Topics] 8525Smart:
I will try to give my opinion as best as I can. I think I have a bit of experience in this area - mainly because I went through the exact same issue and I made a choice. As one can see in my signature below, my choice became the iPhone 3GS.

Mind you, this wasn't an easy choice. As someone who typically despises Apple and their products (in fact, the iPhone 3GS is the first Apple product I've ever owned), it's not like I decided to switch from WinMo to iPhone on a whim. I thought it over for a period of several months.

Originally, once I realized moving onto WP7S would be impossible for me, I was simply going to stick with WM6.X, then the news starting coming that developers were canceling WM6.X projects (including a few which I was really looking forward to). Even on XDA, there were topics from developers stating concern, and some mentioned that they were going to put some 'major' projects on hold to develop for WP7S instead. So faced with the possibility of sticking with an OS that seemed to be dying even as Microsoft profess continued support, it seemed like moving on would be the wiser choice. Unfortunately, moving onto WP7S would essentially be starting all over for me, and the idea of doing such a thing for a brand new OS seemed incredibly stupid to me.

So I figured if I had to move to a brand new OS, why not choose one that had great support already? A lot of choices went through my mind (WebOS, Android, Maemo, etc), but I ultimately chose the iPhone because I figured it would be the easiest transition.

Ultimately, I think I was proven right. Within a span of two days of owning the 3GS, my primary concern, applications, was almost completely alleviated. As I had expected, the iPhone had a replacement application that was equal (and, in many cases, better) to what I had used on Windows Mobile. Additionally, many of my other concerns (lower res, on-screen keyboard, browser, etc) turned out to be fine. In fact, it was often better than I would have hoped for. Even my biggest fear, having to use iTunes, turned out to be very minor.

For someone who typically hated Apple's design philosophy, I was extremely impressed with how they designed the iPhone.

Of course, not all was completely well. Even as I am an iPhone owner, I'm still trying to use the iPhone like I used WinMo, which, of course, just plain doesn't work. It takes some adjusting, but it's admittedly not too bad (it also helps that some fine folks created apps to help the transition. :)). The only other problem I see on hand is Apple's infamous restrictiveness...and I'm not even referring to the App Store. For someone with a mild OCD of keeping all my files neatly organized; Apple's refusal to allow me to even do something as simple as even renaming my files is aggravating. However, I am getting used to it.

So to get to the point, I ultimately switched to the iPhone out of 'lost hope' for Microsoft's platform, and the belief that the iPhone would make for the easiest transition compared to other OSes. I will continue to pay some attention to WP7S to see if it's ever worth coming back to, but if my experience with, well, Windows Mobile is any indication, a year or two of owning the iPhone, and switching will be almost impossible unless Apple does something extremely drastic. To the TC, am I recommending the switch to the iPhone? Ultimately, I think it is your choice, but if my experience is something to go by, switching to the iPhone may not be as big of a deal as one might think. Hell, you might even enjoy it.