I have to say the whole E2.0 thing leaves me a bit cold.
When we deployed blogs, wikis and forums at the BBC we kept the tools separate and kept them simple. I would still maintain that it is important to keep social tools in the enterprise simple. Most people I meet find the whole thing confusing and I am often told how intimidating they find Sharepoint and even Jive.
The important thing is not to have shiny, state of the art, tools but to have people using them. You have to do everything it takes to reduce barriers to entry.