I found the best site to compare 2 different phones. All facts, no opinions and no commentary. Its pretty unique and gives pro reasons for both phones. Try the Lumia 920 vs iPhone 5. (12 reasons for the iPhone 5 and 17 reasons for the Lumia 920)
That site is good, but it only lists specs. Doesn't really say what the specifications mean or why does it matter. The features section is a little suspect..
I am not sure why that site lists Facebook integration for iPhone and not for when Lumia had it two years ago.. (not that I use FB anyway) And that site lists iCloud service for iPhone and not Skydrive integrated into WP8. Same with Siri and not listing TellMe. I am not sure if these are honest omissions, but it would seem if they want to be 'fair', they would have listed these.