I should have an iPhone 6+ arriving at my door on Friday. I will say the new iOS 8 is stellar on my 'old' iPhone 5s and iPad Air in release form as of today.
It's an ecosystem thing for most folks, if you like what you have then stick with it, if you don't you can try an/other side.
Anecdotally, a buddy of mine got an LG G3 a couple of months ago. Nice phablet, big and beautiful screen, all because he 'couldn't wait' and as of a few weeks ago is regretting it, but he was an Apple guy to start out with.
I've been an Apple guy for over 30 years so I'm not likely to change now, and given the experiences I go through on the enterprise side with BB, Windows and Android there is no compelling reason for me to even consider it.
There is something to be said for trying them all, if you want to do that then have fun.
Having said that, from an ecosystem standpoint on both the personal and enterprise side there's nothing that holds a candle to what the folks in Cupertino are doing presently. Maybe one day that will change.