You may seem them here, or some where else, the AdSense holiday themed ads are now live. Basically you will notice them, when you see a faint background image in the ad units. Almost all the Google blogs have an entry on it, but I will only link you to the AdSense Blog's entry Flair for your ad units which shows a picture of an AdSense unit that is popping up all over the place.
Forum discussion at Search Engine Roundtable Forums and WebmasterWorld and DigitalPoint Forums.
