The new issue of Usability News (Department of Psychology, Wichita State University) has some great articles, and, hey, they do research and conduct tests under controlled conditions and compile, like, software usability analyses. Unlike you or me.
My current two favorites from the new issue are:
Reading Online News: A Comparison of Three Presentation Formats
"Accordingly, this study addressed the question of how information should be presented within a news-style web page. For example, should all the information related to a single article be presented on one page, or should the newsletter contain a page that lists only the link titles that relate to each specific article, and which is presented on another page?"
Top Ten Mistakes of Shopping Cart Design
"6. Requiring a user to REGISTER before adding an item to the cart. Some sites we have tested require a user to register with personal information before an item can even be placed into the cart! This is a turn-off to users who may be browsing or comparison-shopping. They may or may not purchase the items, but they definitely do not want to commit personal information just to fill the shopping cart and will leave the site because of it."
Hey, B2C sites! That last link is great and you should read it and implement changes as needed. Don't worry if it takes you a long time to upgrade your cart, I'll just wait to buy from you until then. No, really.