Yahoo spying on you !!
 

Yahoo is now using something called "Web Beacons" to track Yahoo
users around the net and see what you're doing and where you
are going - similar to cookies. Take a look at their updated privacy
statement:

http://privacy.yahoo.com/privacy/us/pixels/details.html

About half-way down the page, in the section "Outside the Yahoo!
Network", you'll see a little "click here" link that will let
you "opt-out" of their new method of snooping. I strongly recommend
that you do this.

Once you have clicked that link, you are opted out. Notice
the "Success" message the top the next page.

Be careful because on that page there is a "Cancel Opt-out" button
that, if clicked, will *undo* the opt-out

Some information on Google

http://www.google-watch.org/bigbro.html

Thanks for the info, I sucsessfully opted out :D

The opt-out is cookie based. I guess yahoo wants people to opt-out to protect their privacy, then also clear their cookies to protect their privacy.

End result: Advantage, Yahoo!.