In an interview Loic Le Meur says, that he does not know of any book about blogging in Germany. So I added up some information for him:
Das Blog-Buch (by me)
Blogs!
Blog for this book: blogbar.de
Online-Communities, Weblogs und die soziale Rückeroberung des Netzes
Die heimliche Medienrevolution – Wie Weblogs, Wikis und freie Software die Welt verändern (TELEPOLIS)
Thanks for the fact checking, I really had no idea and should have checked before.