Very interesting comment. Remember Groupwise or Lotus Notes - the whole groupware craze? This is a great argument for a tightly controlled proprietary internal communications system and I wonder if we might see a resurrection of the groupware fad.
I'm not sure if Basecamp, Backpack, and Highrise are technically groupware but that's what I consider it. But really, these are all tools and there's no magic bullet. We just have to find a way to use right tools for the right job and make sure those we work with understand that each tool has its purpose. We'll have to explain to Joe Staffmember that email is not Google Docs and Skype isn't always a replacement for the telephone, etc.