To be honest, I do have RSS feeds of the newsletters that I don't promote (unless people specifically ask). I haven't put much effort into them for two reasons: 1) I'm trying to get the e-mail side of things 100% right rather than spread myself too thin, and 2) e-mail is a lot easier to monetize nowadays (think mid/high double digit CPMs rather than the $5 or so I make on my Web properties).