The data standardization within Google Product Search has put like products from very large retailers capable of deep discounts in the same page product lineup with smaller merchants who cannot compete on price. The smaller merchants who would generally seek to make their listing somewhat unique to grab longtail product searches can no longer do that. Smaller merchants in the product lineup with Pet Smart for example, have few options to elicit a click from a searcher.
Google recommends that data feeds be under 20MB for upload within Google Merchant Center, while scheduled fetch and FTP uploaded feeds can be up to 1GB. Compressed feeds must be under 500MB or you will need to split them in to 500MB or less files.
Many of my sitemap submissions are gone! Sites, such as PRO-Webs which has been live for years and years suddenly have no sitemap in Google Webmaster Tools. Now, I do check Google Webmaster Tools rather infrequently, but last month the sitemaps were all there, alive and well.
Lastly, to help the search engines understand the actionable nature of your product pages you should includes words such as “buy”, “purchase”, “shop online” etc. When including these types of action phrases it will be most effective to string them along a keyword for the product. something such as “When buying a roo online, you have several options for color, size and delivery”. It’s way too easy to get spammy when trying to create actionable content… so pay close attention to the perceived intent of the words you chose.
The problem? Google has first alarmed the user with strong, scary text (Severe health issues are found on your site), images and colors. Secondly, telling the user that an archive page for example, blocked in robots.txt is an “important page”. So the user, who is probably just a business owner…. Hurries to pay their IT guy to unblock this “important page”, so Google can omit it from the search results for duplicity and “low quality”.