Users Don't Know (and Don't Care) What RSS (or Ajax, or CSS...) Is
Jakob Nielsen nails a point that has been made by many others in his most recent column on newsletters. Most people don’t know what RSS is, even though they may already be using it via MyYahoo or some other portal. The typical user doesn’t know (or care) about RSS, HTML, CSS, or Ajax or any of technical details that you and I live and breathe every day. If you use jargon and techno speak in a site with a general audience, you can expect your usability to suffer.
Nielsen also touches on something that many fellow nerds already know about RSS feeds - they are a “cold medium” compared to email newsletters. Emails can create a personal connection between a company and a person when done right. Feeds, in all their plain text glory, take away all context and reduce a business or organization to its basic info. This is great for scanning and getting your fix, but sucks if you want to make an impact with your brand or finely written, two thousand word articles. So the rule for newsletters (email or feed based) should be very much like an effective blog - write great headlines, keep it simple and short, and make it easily scannable.