The Pioneers: (formerly The Founding Fathers): industry luminaries who created the vision of open media and continue to shape it.
The Tool Smiths: web service entrepreneurs and companies building the open media tools (blogs, social software, wikis, RSS, analytic tools, etc.).
The Trendsetters: the influencers driving and evangelizing the adoption and applications of Open Media.
Marc Canter & JD Lasica
The Practitioners: the top bloggers in politics, business, technology, and media.
The Enablers: the venture capitalists and investors backing the Open Media Revolution.
Update: Jeneane’s points are well-taken.
Update 2: Peter has a great list and more dead-on comments–probably shoulda been the 200..or not happened at all.
Those Bastards has the best take on a more cynical viewpoint, via mobile jones .
Another good (and amusing) list from Barb D.