Retina Macbook Pro now has faster battery drain
Reboot.
Create a new user.
Try.

If the battery life is still short after a couple of days under a new account and there's nothing weird. Take it back to an Apple store. They will run the hardware test and determine if there's a problem with the battery. Be nice to them. Explain them that you know what you're doing, that this is unusual, that you know how to take care of a battery, that it suddenly started happening and that you would like for a Genius to take a look at it. 

I did that with my Macbook Air 11 (with a 8 month old battery that just died out of nowhere) and they kindly replaced it. 

Better safe than sorry.