RSS feeds - Part 1 & 2
I think they have great potential for liaison librarians who can subscribe to numerous feeds to keep up to date with trends, resources and news in specific subject areas. Rather than roving aimlessly through site after site looking for useful information you can simply select each relevant feed to come to you!
I'm not so sure about the RSS search tools - on quick inspection there appears to be a lot of commercial sites and not a lot of academic content.... such is life on the internet...
I do like Technorati - blog searching by subject seems to extract some useful content. I think co-workers and library networks would also be a very efficient and reliable source of quality RSS feeds.