http://cheesemonger32.googlepages.com/jimp.png

I know the grey iTunes button has been spotted before in the US, but I think the Advert overlay is new. The dropdown list only shows iTunes, I guess others could be added but I can't find a video with any others

<<Today we're expanding the program beyond the US and the UK. Links to songs from the iTunes Store will now appear in Germany, Spain and the Netherlands, so users from those countries who are drawn to a particular song can easily purchase it. (...)

We're also expanding and improving the ways in which these links are displayed. You may start to see click-to-buy links appearing as semi-transparent overlays that appear in the bottom of the video for a short period of time. This increased visibility should help even more people take advantage of this program.>>

http://www.youtube.com/blog?entry=n-q9Enl2O2Y