Windows Phone 7.5 is quite competitive from iOS 5, and which you choose may very well depend solely on your preferences. If prefer more apps or the safety of numbers, the iPhone and iOS is where it's at. But if you want a truly superior software experience, Windows Phone is the obvious choice. Hardware, for now, is a question mark, but I'll give Apple the temporary thumbs-up until we see what Nokia has done. --Paul Thurrott
Obviously he's a blue-blooded Microsoft-er, so take it for what you will, but I encourage you to look at his whole review and see if you think he kept his bias in check. A good, thorough comparison nonetheless.
Maybe there'll be a fiery rebuttle from some iOS blogger out there.