Google is experimenting with new ads around their services. Recently, you may have seen in my Tech News Flash that Google is putting apparently 'intrusive' adverts in GMail. So here's another space they have devoted to advertising that I have noticed.
There's a wide and huge bar at the top of Google Images results. It appears only sometimes, but takes up lots of space with an image thumbnail. I find that intrusive.
Let's see where all these tests reach. I hope Google doesn't start messing with user experience while displaying ads.