I think the context is slightly different: when an employee says "we do not track users on other domains", he means that they don't record your loading of a page with a "Like" button, even though they could. The patent claim is for a system with facebook "receiving one or more communications from a third-party website [containing] an action taken by a user", which they then incorporate into their ad-serving wizardry.
This could be quite interesting, actually: imagine facebook launches a system where any third-party website can give it a stream of "actions" taken by facebook's users, and pay them based on how good the data are for predicting ad preference. Site owners would then have a financial incentive to report to facebook every single thing their users do.
Imagine if HN did this, reporting to facebook the literacy level of your comments, the speed at which you read the comments, what subjects you spend the most time reading, what you comment on, etc.
This could be quite interesting, actually: imagine facebook launches a system where any third-party website can give it a stream of "actions" taken by facebook's users, and pay them based on how good the data are for predicting ad preference. Site owners would then have a financial incentive to report to facebook every single thing their users do.
Imagine if HN did this, reporting to facebook the literacy level of your comments, the speed at which you read the comments, what subjects you spend the most time reading, what you comment on, etc.