Philipp,

It slows down your page loading.

Hey,

We don't inline styles because we give designers complete control over the styling of results and controls. This is how sites are able to get such seamless integration. A great example of this is a site like http://success.salesforce.com/. Notice how well integrated the search form and search results are on this page?

Anyway, in your case, you have a blanket rule adding a bottom border to all td elements.

It is nice. Can make the site more content and pleased the users. Wish more Good Google.

Edit: The widgets stalled IE6, so I replaced them with static images. An update has been added to the post.

Amazon has a similar feature as part of their associates program that does give you compensation for sales through the links. It is called "Recommended Product Links" and lets you show a selection of books based on keywords or categories.

http://affiliate-program.amazon.com/gp/associates/network/build-links/dynamic/main.html

From the page:

Recommended Product Links feature products chosen automatically based on product categories or keywords. To create a Recommended Product Link, start by selecting a product line. Then, either enter some keywords or choose a product subcategory, and click Continue. You'll then have the chance to pick a size for your link and further customize its appearance.