Information we collect
* The Google Toolbar automatically sends only standard, limited information to Google, which may be retained in Google's server logs. It does not send any information about the web pages you visit ( e.g., the URL), unless you use Toolbar's advanced features or use Safe Browsing in Enhanced Protection mode. You do not need to provide any personal information in order to download and use the Google Toolbar.
I have explicitly turned off all of these features, but it still sends URLs.
Here's an example: if I visit a web site like http://wikipedia.org/ , and Live HTTP Headers shows (some info masked):
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:18.104.22.168) Gecko/20070718 Fedora/22.214.171.124- 1.fc7 Firefox/126.96.36.199 pango-text GoogleToolbarFF 3.0.20070525
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q= 0.7
HTTP/1.x 200 OK
Content-Type: text/html; charset=ISO-8859-1
Date: Mon, 06 Aug 2007 15:32:25 GMT
My Google Toolbar, as much as I used to love it, disappears today."