The Pew Internet and American Life Project report on the State of Blogging, reports at this time that only 5% of Internet users say they use RSS aggregators or XML readers to get news and other information online.
Pew also reports a 58% growth in blog readership (27% of Internet users say they read blogs). In my opinion growth in the usage of RSS tools by the typical Internet user will continue to lag until the value of the tools for managing information is better understood.
Blg writers use RSS to gather information needed to feed their blogs. The typical Internet user does not have this same hunger for news. RSS applications such as Pluck that through its Persistent Perches allows auction purchasers to monitor price changes will make the value of RSS accessible to more typical users of the Internet.
I eagerly look forward to seeing the next set of stats on the growth of adoption of RSS.