Esther just asked for a show of hands. How many people use only proprietary software? How many use a mix of proprietary software and open source software? How many people use only open source software. The guy in front of me raised his hand to the last question. I looked up to see what he was running on his IBM Thinkpad. Windows 2000. The open source version, apparently.

Good stuff today on presence -- a very interesting concept -- and search.