It seems Google is testing a new user interface for Google Images image previews. There are reports of this test at both WebmasterWorld and DigitalPoint Forums. As you can see from the image below, after you click on an image from Google Images, you are then taken to a page that lets you click on left or right arrows, to slide through the various images.
I personally cannot replicate it. It seems to be something being tested from outside the US.
As you can imagine, webmasters are not happy with this new feature. They believe it will result in a drop in traffic from Google Image search. One webmaster said:
This changes everything! - before - a well placed image would bring in traffic - and a enough revenue to cover costs - etc. Now the image is in a gallery (Bing style) - I imagine click through rates will be negligible to the host page, context is lost, any copyright notifications gone, and no protection for the image.
The information from the site is just a small panel to the right.