It seems that people are missing the point with this technology.
Think about all the enterprise services that this spans. I'm seeing a Sharepoint, Exchange, and LCS killer here at a minimum. I was hoping to see Google Video/Voice chat mixed with this, but I would say that it's probably not too far off. If it had that, goodbye to WebEx, Genesys, etc.
This is a collaboration tool, and that's it. There's no spam in a controlled audience. Even where this thing can be exposed like blogs and wiki sites, you have complete control over what gets included and published.