2011 528i (new member)

Last Saturday I traded my 2004 525i (23,000 miles) and purchased the 2011 528i. I must say, there is a lot to learn, but I really like this car! Can anyone give me some advice on the electronic key / and battery drainage? I am basically a weekend driver and my condo has valet parking. I have to remind the attendants to store my electronic key in the office (not my car!). Are there any other concerns I should be aware of?

Thanks!