I refuse to use any Android device that is not running the stock version of Android, so I would never go with a Samsung device. I also refuse to use an Android device until every single device running Android is running the exact same version of Android, that looks exactly the same across every device. Which won't ever happen. No "Google Play Editions" or doing all that Boot ROM-thingamagiggering either. For me, it's Google Nexus or bust.
But I will still pick the iPhone over other devices because I've invested a great deal of money into the Apple ecosystem already, and I'm very happy with the performance of my iPhone (battery could be improved though!)
But an even bigger thing for me is software design. I like how Apple designs their software (and hardware) but their design is much more appealing to me. It seems like anybody else throws in ugly pointy boxes, or has too many buttons, ugly icons, command lines, and just general ugliness.
I also really love iCloud. Syncing everything across all my devices that easily, and accessing everything super easily with no horrible confusing menus or anything is the best thing ever. Plus I really love how well iCloud integrates between my Mac and iOS. Starting something on the iPhone or Mac and picking up on the opposite device. Great.
Why on earth does it matter to you which version of an o/s someone else has on their phone? As long as yours works as intended, I see no problem. You have also basically said that no matter how amazing Android may be, you're sticking with iOS because you have a Mac and you're entrenched in the Apple ecosystem. That's hardly a balanced and non-biased viewpoint is it? Plenty of Android users have bought Google Play apps, use Google services on their laptops and are 'entrenched' in the Android/Google ecosystem. The fact remains that if anyone is starting afresh in 2014, both platforms are an attractive prospect. Android arguably more so.