Google started to display a thumbnail in the Product Search OneBox, as you can see by searching for [usb flash]. The image illustrates the top search result, but links to the list of results. As part of the Universal Search, this OneBox can be displayed at the top of the search results page or at the bottom of the page, depending on its relevance to the query.
Another change is that the OneBox groups identical tech products and shows a range of prices. For queries that include clustered listings, Google no longer shows a link that restricts the results to products that can be bought using Google Checkout.
Here's an old screenshot of the Froogle/Product Search OneBox:
