Google is now testing a new feature called "Instant Ad Previews," that allow Google users to preview the AdWords ad's landing page before clicking on an ad to visit the site.
As you can see, all of the ads on the screenshot -- whether above the organic results or in the right column -- are showing the small magnifying glass icon for Instant Previews. The preview image itself seems to be work exactly as the feature works in organic search; the search query, "lcd tvs" in this case, is called out and shown in bold on the preview.
Just as with regular Instant Previews, Google users seeing the test can simply click on the magnifying glass next to the ad to see the preview page and call outs (the orange boxes) highlighting the search query [lcd tvs] on the landing page.
[Image Via: SEL]