Adam clears up much of the concern with the call for paid link reporting. As with any spam report, it’s not going to be used for direct action. Link reports are there to use as a benchmark when modifying the algorithm in an attempt to thwart similar spam actions.
Again, that’s because this is used for periodic testing and review. But, on the reassuring side, we’ve had some people voice concerns “what happens if my competitor decides to report my pages, even though they are completely following the webmaster guidelines. Is some action going to be taken?” The answer to that is definitively not, because this does not lead directly into an action pipeline, but rather it is used only for review. It is not going to directly or adversely affect any pages or sites that are following the webmaster guidelines.
Adam also dispels the myth of duplicate content penalties. Duplicate content would need to rise to the level of black hat, full on spam attempts for a penalty to be assessed. Those printable versions of your shopping pages, while not helpful to your rankings, are not going to get you charged with an actual penalty.
I will reiterate my initial comment, that in the context of duplicate content, penalties tend to be relatively rare. In the majority of cases it is innocent and unintentional. But, in cases where it’s very extreme, there can be penalties applied. It comes back to what I mentioned earlier which is whether or not the duplicate content passes the smell test. It’s very much related to issues of quality as well.