Actually, Now's time goes under Maps- at least the location services, which are the big draw. I have all of the tracking enabled, and maps uses between 20 and 30% of my overall.
Interestingly, GSam battery monitor (which I just got last week, and is really neat!) shows the number of times each app woke the device. I've been on for 4.5 hours, and Maps is at 441, with the next Android System at 85 and Google Search (which is Now) at 53.
Android System has also shown up more in usage % since I started having Now.
I think there's definitely a significant drain with Now. I've had it enabled since the Verizon release, somewhere around 12/20, but I think I will disable it at the start of next month and keep an eye on how it behaves. I certainly feel that my battery life has gone down since the upgrade.