If you're a Store owner who is interested in providing listings via RSS feeds, go to "Manage My Store > Listing Feeds (within Store Marketing)". Click on "Distribute your listings via RSS" and click "Apply". The RSS button should appear on the lower left hand side of your Store.

Specifically, Marketplace Research can provide buyers and sellers with average item prices, show top keyword searches by category or related keywords, create charts illustrating transaction trends and deliver data on completed sales over the past 90 days, according to the announcement, posted by John Bodine, an eBay product marketing manager.