Dr. David Wyld from Southeastern Louisiana University has written an interesting report, entitled The Blogging Revolution: Government in the Age of Web 2.0, in which he takes a brief look at the history of blogging in government. Overall, he has done a pretty good job of covering the topic in the last few years, although he misses some of the very interesting things that happened back in 2002-2004 and some of the rationale behind tech bloggers in government with more of a focus on the political bloggers that came later and entirely misses some of the best international egov bloggers like John Gotze, Alan Mather, and Carlos Guadian. Overall, he does a very good job of capturing the more recent history however. He also has some interesting thoughts on RFID.
Here's an executive powerpoint of the report which is covered here, here, and here.