Scott Gatz has word that Yahoo! will be adding an RSS reader to Yahoo! Mail. He writes,
RSS in mail makes perfect sense for a few reasons: 1) people already spend a lot of time in their Mail experience, why shouldn’t personally relevant content be there too 2) While you read RSS you are probably gonna want to forward good stuff you find 3) Hundreds of millions of users use Yahoo Mail, so if we want to reach the masses, we need to go where they are.
It makes perfect sense. The big guys like Yahoo! are racing to be the primary source for large-scale RSS feeds from all sorts of different sources. They're going to find a way to make this work, and they're going to do it in a way that's invisible (and simple) to the casual user.