[terramoto]

Arent they just sharing metrics like ad x was seen y times in b place? If that's the case I think that's a good compromise. Sites that don't sell anything need to make money some way, if all they want to know is if an ad in a certain place about a certain product is working or not, that's fine by me.

[autoexec]

No, the browser tracks what ads you see/click on, then monitors what you do online for signs the ad was successful, and if it thinks it found one it sends all that data to a third party who compiles a report to deliver to the ad company.

That might be okay to you, but a browser that snoops on my browsing history and reports it to third parties who will then use it to send reports to advertisers is totally unacceptable to me.

[robertlagrant]

It only does that for websites that are funded by advertising. If you avoid those (e.g. HN) you should be fine?