Battery drain over night while sleep mode

[TheSponge]

Is it normal that when the macbook is in sleep mode at 100% battery life after about 8hours it's down to 80%?

This is a 2011 Macbook Pro 13", the battery is brand spanking new Apple OEM that was installed at an apple service centre, I've only put 1 cycle on it.

Because my previous late 09 macbook, would barely go down overnight while in sleep mode.

 

[johnnnw]

Doesn't seem normal. Are you sure it's actually sleeping?

I think mine drops a few percent when it's on overnight in sleep mode.

 

[TheSponge]

Doesn't seem normal. Are you sure it's actually sleeping?

I think mine drops a few percent when it's on overnight in sleep mode.

Well its not my first mac so I think it is fully sleeping?

I've never owned a Macbook Pro, I've had a 2006 Black Macbook and a 2009 Macbook. Now unless there is something this new macbook has for a setting that I am not aware of?

Also, could it be the fact that the battery is brand new? I've just had it installed last week and only had a chance to use the macbook pro for the last few days a lot..

I should also note, I am running Mountain Lion.
Here is a screencap from the Power tab in About this Mac