I carry my N7 with me at work, but seldom use it at home. When it's home, it's asleep, but I've noticed that if I don't completely power it off or plug it into the charger, even if it has a good charge on Friday evening, the battery will be dead by Monday morning.

I've turned off Bluetooth and location services, but it still drains over time even when not in use. I also have an iPad and I do not see this happening with it -- the iPad can be asleep for several days (even when Bluetooth and GPS are turned on) and still have a decent charge when I wake it up...