Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
To be fair, no one has tested the iPhone 6+ yet. I wouldn't be surprised if Apple let it draw more power with how much extra capacity that battery has. Only way to know for sure is to measure the current draw with a 10W or 12W charger

I did. It draws around 10 watts depending on if you're using the phone or if it's just charging.
 
Hmm I have 2 iPad chargers 10 w. Guess I should use those to charge my future 6?
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.