Om Malik is putting people onto Downfly – a social link exchange service with a twist. Not only does it make it very easy to send links to your friends from any page or application. To get an idea of how easy, and social this is check out this little promo:

According to Om it can also::

 “track where those links go, i.e., if any of your friends forward them to others.“

Boy is there value in that!

It could be like Nielson’s or Arbitron for viral ads and commercial referrals. And imaging how commercial connections could change if referrals replaced ads, or even if the metrics gathered were aggregated to measure effectiveness, reach and potentially psycho-demographic characteristics associated with interest in the link.

Don’t worry – Downfly isn’t doing this – in fact thier terms of use and privacy policies are squeaky clean – they notify you that they may put advertising on the site.

Which is a pity, the aggregated data they could gather is way more valuable to marketers, and way less intrusive to you.