Ever since Google admitted they read peoples emails so they can sell their info to companies for direct advertising, I try like hell to stay away from anything Google does.
Marty
Here's how the wiki characterizes it:
Google automatically scans emails to add context-sensitive advertisements to them. Privacy advocates raised concerns that the plan involved scanning their personal, private emails and that this was a security problem. Allowing email content to be read, even by a computer, raises the risk that the expectation of privacy in email will be reduced. Furthermore, email that non-subscribers choose to send to Gmail accounts is scanned by Gmail as well, even though those senders never agreed to Gmail's terms of service or privacy policy. Google can change its privacy policy unilaterally and Google is technically able to cross-reference cookies across its information-rich product line to make dossiers on individuals. However, most email systems make use of server-side content scanning in order to check for spam.If you believe that (I do) google doesn't sell you information, rather, they match their advertisers to their email customers, and
put "relevant" ads up for you to see. I like motorcycle ads more than I do ads for depends, but that could change

...
Anti spam programs read all our email, I don't really care about Google's ad-matching programs... google mail is free to me,
but nothing is really "free"...
What I hate is cookies... especially tracking cookies, and especially third-party-tracking cookies... I think that's
the way that slimy people (people not programs) are building up information on us.
I make web sites ask me before they can set a cookie, and now that I know just a tiny bit about third-party-tracking cookies,
I usually "just say no". Cookies make shopping carts and other stuff go, so some web pages you might care about won't
do right if you don't let them drop cookies...
-Mike