Google Is Retiring AdWords Product Extensions.
See the following links for more information (though there is nothing official on the AdWords support site yet) :-
What difference will this make? Not a lot. The main thing is that you will no longer have to assign a product extension to a non Product Listing Ads campaign in the ‘Ad Extensions’ tab in AdWords.
Update – here is official confirmation from an AdWords campaign view on 16th May 2013 :-