My first Galaxy Nexus used to get 14 hours consistently with 3 hour screen on time without ever turning off data. I sold it and recently purchased another one and this one goes 7-9 hours with only 1.5 hours of screen on time. I think im going to take it to Sprint to get the battery checked out.
Weird. Keep us in the loop on what you/they find.
Sent from my Samsung Galaxy Nexus 6.