I am primarily a single player gamer. The fact that the next Xbox will disable my game if I'm not connected to their server is unacceptable. Both my 360 and PS3 are currently always online, but there are certain times of the year where my area suffers frequent blackouts. The last time, during Hurricaine Sandy, the power was out close to a week. I. Have a smal generator that can run my fridge and I've made room for a TV and an the PS3 or Xbox to run and this kept my family somewhat entertained during those times. Going forward, the Xbkx won't be an option for times like that.
I'm also adverse to the thought of adding another monthly bill.
Comparisons to the iPhone are flawed because I can actually disable the Data Usage on my iPhone and sti make calls and 90% of the apps I have will still work. The Xbox will basically be a paperweight at that point.
I'll eventually get both, but PS4 first and foremost for me.