It has reached a stage where the only difference between smartphones will be how rugged/thin/large/pretty they are. The OS will be a matter of preference, the fanboys for each OS will talk about how wonderful and advanced each OS is and how much better it is than it's competitor, but none will have enough of a differentiator to make the stand on the fence purchaser jump. Even speed and memory will not make the difference since the current speed is fast enough now, the super fast cpu/gpu's are now more necessary to drive the OS and the power the refresh rates of the these high resolution screens (that we all want and must have).
So we are back to how pretty the phone looks, or maybe does I have a bottle opener on it, or can it make my coffee??
I suppose the next great innovation will be smaller run cool last forever batteries, now that would tempt me to change
If you are a Apple lover then drool away. If you aren't then more than likely you will skim over the article and move on. I love my S4 and the Android Platform, am I drooling over the S5, hardly, would I love to have or play around with the S5 or maybe even the iPhone6, sure why wouldn't I.
Of course Apple will be big, because so many people will go buy the latest and greatest just because. Do they need it, can they afford it, does that even come into consideration these days, I doubt it. People upgrade cause they can not cause they need to.