From the indefatigable Anne Holland at Marketing Sherpa a report on best practices for conversion rate. She went to a web analytics conference where the attendees spoke up about what works for them. They should know, because they actually measure it.
Some ideas to think about:
My favorite snippet:
A panel that included a marketer from Macromedia concluded "95% of Web marketing design using Flash is inappropriate - it's not helping the visitor scratch their itch." However, one panelist said if you're marketing to Japan that may not be true.
Japan is just a cultural signularity. That's why it's so fun.