Jakub Linowski, creator of Wireframes Magazine just started writing a newsletter called Good UI on how to design sites that are easy to use and also yield high conversion rates.

He's looking at how to employ practical ideas that satisfy the business side as well as the people using it, which I'm sure is something we all want to do on sites that sell a product or service. He plans to publish the newsletter monthly. Check it out.

http://www.goodui.org