Google likes to watch...

Google doesn't want to be evil... but The Corporation is evil by design.

So their latest thing is finding ways to watch where you are going on the web.
Internally I'm sure this is justified as a way to improve their link rankings.

Google started with the Toolbar with PageRank turned on.
In order to calculate PageRank for each page, it has to contact Google and tell them what page you're visiting.  To be fair, it does put up a privacy notice.

Then there was Sidebar, which also seems to know what you're looking at.
There's also desktop search and such.

They try to offer you "free" functionality in exchange for knowing where you are going.
Now there are a couple handy Firefox extensions:

• Blogger Web Comments for Firefox The Blogger Web Comments Extension sends the URLs of pages that you visit to Google, so that we can search for and identify blogs that talk about that page.
• Google Safe Browsing (USA only).  An anti-phishing toolbar. If you enable Enhanced Protection, the Google Safe Browsing Extension will provide more up-to date protection by sending the URLs of sites that you visit and limited information about the site content to Google for evaluation.

So just be aware of this, when you're installing new Firefox extensions and such.

via Google blog - New Firefox extensions
Note: Google blog links are broken, I only got there from Google Labs - Google Extensions for Firefox.  It seems the links don't work without "index.html" on the end at the moment.

Also consider Google cookies: the search pages themselves want to drop cookies.  The toolbar wants to give you a cookie.  And of course, Google Analytics is in a whole other league of user tracking, including pushing a cookie (to, amongst other things, distinguish new visits from revisits).

But a while ago I noticed that the Google Blogger button, you know, that harmless "I Power Blogger" button you have to put on your Blogger pages?  It started pushing a cookie.  And all BlogSpot pages started pushing a cookie.  Err, how many cookies do we need exactly, Google?