Visual Hierarchy is the Art of Managing, Not Eliminating

A few months ago 37signals redesigned Basecamp's notification emails, and the result was a move from plain-text emails to HTML emails. For reference, these emails are sent when someone posts or replies to any of the content types in the system (messages, to-dos, etc).

I'm generally opposed to receiving HTML emails if a plain-text alternate is available. I use email as a tool to send and receive communication, and too often some creators of HTML email offer visual noise more than anything...