I just set up an RSS aggregator using Bloglines. I used the Bloglines "Quick Picks" option to select sports. It was really neat how this option selected the best feeds from the major news sources such as ESPN and CNN. At first it seemed like information overload, but it is nice to just see headlines posted without having to sort through distracting advertisements.
I think RSS has great potential for Extension. It is a great way to distribute information rapidly. I think the most difficult things about using this new technology will be to educate the public about how to use it, and then make them want to keep using it. While RSS is nice, it is one more thing to check each day. For this reason, I almost prefer email alerts rather than RSS unless I have additional time.