Inside AdWords: Six weeks to set your time zone: "Six weeks to set your time zone
Last night we released AdWords local time zone support to all advertisers. Now you can set the time zone that you prefer for your account. Doing so will enable your ad serving, reporting, and billing to be calculated and managed according to the time zone of your choice."
If you use adwords, then you will want to subscribe to adwords.blogspot.com by Google's adwords team so that you can keep up with their latest. But, be careful and ask a veteran about any changes you consider based on that information as it is meant to make Google money...
To your Success!