I recently posted about the concept of "Superdistribution" on Smartmobs.com  -  using Using Superdistribution to Socially Sell Songs.  How would we track that?  According to MarketingShift

"Friends can share or lend music with each other, and the files are locked by digital rights management software for limited time use. People have to pay for a key to unlock the files for permanent use, and the friend who shared the music can get credit towards future purchases."

"…..Imagine if YouTube videos could be easily downloaded and shared between iPods and cell phones. Advertisers would salivate for a five second pre-roll before these viral videos. Google and MTV recently announced a deal for promoting videos that touches on superdistribution."

Ok, so in the future, when superdistribution becomes the norm - we’ll have to measure not only the download of the music / video / pdf file - but also find a way to measure how much the file is being superdistributed to other friends - who inturn, might not need to download the music / video/ pdf file because they already have it.

I think it’s another example of how difficult a time web analytics platforms have in keeping up with new ways to share information.  Right now, few web analytics vendors offer tracking of RSS Subscribers (we all know how big that is going to be in the future) or podcast / vidcast downloads.