I keep saying it, don't trust that your PR firm knows how to deal with bloggers and the blogosphere unless they have some knowledge and practical experience. You cannot "get it" unless you do it.

Here is a list of early pioneers from the Bivings Report. BTW, even if you start blogging now, you will still become an early pioneer, we haven't yet begun ...  :-)

Waggener Edstrom
April 1, 2003

Burson-Marstellar
July 26, 2004

Edelman
September 24, 2004

Hill & Knowlton
December 2, 2004

Schwartz Communications
January 1, 2005

MWW Group
January 9, 2005

Manning Selvage & Lee
April 27, 2005

Horn Group
May 12, 2005

Ketchum
September 27, 2005

Ogilvy PR

Link to PR Firms That Blog: Who Got There First » The Bivings Report

Update: Trevor Jonas from Bite Communications says Bite has been blogging since February 2005. http://blog.bitepr.com/