Currently Being ModeratedDec 8, 2012 6:34 PM (in response to Herbert Spencer)
Whenever you have any bluetooth device actively paired, the iPad will use more power then without the device being connected, yes. An active bluetooth connection requires the bluetooth radio to run constantly.
Currently Being ModeratedDec 8, 2012 7:06 PM (in response to Herbert Spencer)
My experience with using a BT keyboard is that it has a negligible affect on battery life. The connection drops if I'm not using it for a while and picks up again when I start typing. I am using a Logitech keyboard designed specifically for iPads.