I ran across a great resource for external-facing community managers: List of Social Computing Strategists and Community Managers for Enterprise Corporations 2008 –Social Media Jobs and Professionals It's in an invaluable, insightful blog, Web Strategy, by Jeremiah Owyang, who I would certainly cite as a thought-leader in social media.
However, his list expicitly excludes those of us who manage internal communities, so I have started a new list for us in my blog:List of Online Community Managers Inside the Enterprise
I'm the only one on it, so far! Please check it out, and leave a comment on the blog if you'd like to be included in the list. Hope to see you there