yeah, looks like some of you guys are seeing this too. I disagree with what Google said, there's no way that this is adware...I don't have anything running that would do this, neither at home or at work. Also, there is only one particular version of one particular ad that shows this....strange. Maybe that lady from Google wasn't aware of this?
Haven't seen them personally, although I have seen some new "Ads By Google" logos that look nicer IMO.
I'd hate it if someone clicked the X and I'd have all that un-used real-estate on my website! Some sort of alternative should be offered