Don't get me wrong, I LOVE the Operating system, the live updating tiles, the integration between the various social networks. Actually, I've had two Windows Phones the past year - a Dell Venue Pro and a HTC HD7. I would completely recommend Windows Phone to anyone as long as they understand the Two Reasons I Hate Windows Phone. Yes, its a love/hate relationship. We're currently in the broken up stages. I currently have an Android phone.
Reason #1 - Hard Reset
A "hard reset" is basically erasing everything off your phone as if it were brand new. While this may not appear to be a big deal, there isn't a way to re-download all of your apps automatically. Apple iPhone have the iTunes ecosystem where all apps are stored locally, so theoretically, you can just "sync" your phone. While Windows Phone uses Zune (and its great at wireless syncing) if you have need to perform a hard reset, you will be forced to manually download all of your apps via your phone or (online Windows Marketplace).
Why do I need to perform a hard reset?
Your Windows phone is tied to a Windows LIVE email (you don't have to use a .LIVE or .HOTMAIL), but once you set up your email as a Windows Live email, that is set on your mobile device. Recently, my Xbox live account was hacked and after contacting Xbox support, they changed the Windows LIVE associated with my account for "safety reasons" with a new random email. This basically renders your Marketplace useless, if you try to assess application or update your phone - your phone will AUTOMATICALLY provide your current Windows LIVE email, with another Gamertag.
If you aren't a gamer, this probably isn't a big deal, but many Windows Phone users love to play games and probably currently have an Xbox as well and achievement points are just topping on the cake, needless to say changing emails and gamertags is a frustrating experience. There is a workaround, but it will involve you (not xbox) creating another email, associating your current (unused) gamertag to that email and finally associating your email with your original gamertag. Needless to say, I no longer a windows phone after this experience.
Reason #2 - Applications
While the number of applications is just a number to me in regards to marketplaces, there are applications that doesn't exist in the Windows ecosystem that I like to use on nearly a daily basis.
Applications such as Yelp (the Windows version doesn't have a check in method), RunKeeper (an application which tracks your workouts - cycling, running, etc.), Instagram (my current favorite picture sharing application). Check out http://www.windowsphone.com/en-US/marketplace before you decide on a Windows phone - chances are you've invested in an Apple or Android ecosystem and your favorite applications may not be available on this ecosystem.
Microsoft, I love your operating system and I wish you the best with the release of Windows 8, but being an early Windows phone adopter and not having access to the latest and greatest after 2 iterations of the operating system is quite a bit much to bear.
Mahalo for reading.
Until next time.