It can be pretty frustrating to search eBay for commodity items, since accessories and parts are often mixed into search results. For example, a search for "ipod nano" brings back listings for cables and armbands in addition to the iPod gadget itself.

On Thursday, eBay rolled out a Products & Reviews tab that could help searchers, although some caveats apply.

The Products & Reviews tab appears in search results pages only in certain categories: technology categories, Books, Music, DVDs and Movies and Video Games. The tab is located to the right of the existing three tabs: All Items; Auctions only; and Buy It Now only.

Shoppers can click the tab to find a product catalog page displaying various models of the item they are looking for, along with product reviews. Once they find the product they want, they can click to find listings - no more accessories mixed in with products.

As eBay explains, "Use the tab to search and shop for products, quickly compare features, and read user reviews. When you're ready to buy, just click on the product you want and you'll see the eBay product page with all the options available from eBay sellers."

Because the new feature clearly runs off the catalog, eBay sellers who don't use catalog won't get exposure to shoppers using the Products & Reviews tab. And the feature removes the serendipitous nature of the eBay experience, which in some categories in particular - such as books and DVDs - may hinder shoppers from stumbling on items they didn't know they wanted.