I can't find a date of Feb 1, but it has been approved:
http://www.kansascity.com/mld/kansascity/news/local/13314831.htm http://hardware.slashdot.org/article.pl?sid=05/11/01/159241
From what I read, it is more for aggregate data, traffic conditions,
etc. Although they could probably start tracking individual users if they wanted to. If this became more common place and people heard about it, you'd have some upset users.
I've heard that OnStar can't pass on speed info to authorities. Although, they could probably be strong-armed.
Jeremy