I enjoyed looking at the Teacher Library Ning. These pages in particular were of interest to me: http://teacherlibrarian.ning.com/group/schoollibraryadvocacy, http://teacherlibrarian.ning.com/group/web20inthelibraryworld, and http://teacherlibrarian.ning.com/group/elementaryschoollibrarians.
I think this a great networking and idea site. It is a great resource for new ideas or answers to questions and problems. The site did have a few places where people had just posted 'ugly' comments but for the most part it was easy to use and very helpful.