If that's the real issue, then I'm in support of regulation that keeps Google from ignoring attribution in data it shows, but I would be interested in more specifics. I've heard enough horror stories about Yelp! to not take their word for what happened without a grain of salt. The memo you linked makes no mention of this type of issue though, it's about placement of comparison results AFAICT.

Additionally, the first portion of "The Statement of Objections outlines that the markets for general search and comparison shopping are two separate markets. In the latter market, Google faces competition from a number of alternative providers." is something I think is widely debatable. People have comparison shopped with search results from the beginning, Google as been iterating on it steadily and this is the result.

This is interesting: "Google does not apply to its own comparison shopping service the system of penalties, which it applies to other comparison shopping services on the basis of defined parameters, and which can lead to the lowering of the rank in which they appear in Google's general search results pages." I'm not sure what system of penalties they are referring to. The only ones I know of are for blackhat SEO, and if that's what they are referring to that's an interesting argument to make. I wonder how it will go.