Wake from Sleep Slowness

macbook pro late model - non retina....

When I close the screen lid and sleep the computer ovenight - with about 50% or less battery - and then attach power to charge overnight - then open screen lid...

- it shows a whited out screen for 10 sec's and will take over 30 seconds before I can move the mouse

- it seems to be related to = Mac notebooks: About standby mode

http://support.apple.com/kb/HT4392?viewlocale=en_US&locale=en_US

- but it does NOT mention non retina MBP

Q: any ideas what this is about?