Here is a semi-definitive list of web 2.0 applications for churches
Bible search
Blogging
- About Life
- Minor Prophet Bible Blogs
- e-Church (down for total, complete redesign by Turtle Interactive)
Bookmarking
- Sermon Cloud
- Remarkable! (a product of Turtle Interactive)
Podcasting
Productivity
- Cross Connector
- People to Pray
- Plaid (coming soon from Turtle Interactive)
Social networking
Content Management Systems
Credit: Turtle Interactive





I would like to recommend you take a look at Famundo, http://www.famundo.com, as a free web-based calendaring solution for churches. Here is a sample church church calendar for you to view, http://church1.famundo.com
I would reconsider bibleicio.us “Web 2.0″. Useful tool, perhaps, but definitely not web 2.0.