The value of a search engine isn't any particular result, or any set of results. Its the quality of all the results over time. If Microsoft's algorithm picks up a tiny amount of signal (ahem 1 of a 1000) indirectly from Google's results, this does nothing to artificially inflate their position off of Google's back. There's nothing inherently wrong about using user signal for this.
There are many sites on the internet that generate a set of links based on form data. Google is one of many in that respect. This technique is effective in gathering search information on this "deep web". Special-casing Google positively or negatively is the wrong approach here.
The problem is that the small amount of signal that Bing picks up from Google carries more weight for the more rare associations that Google has worked so hard to help users find. Spelling mistakes stand out here quite a bit.
I don't really see this as a problem. This is in fact what search is all about. Some human makes an association between A and B, and a major search engine picks up on that. Google has algorithms for picking up on these associations, and so does Bing. It just so happens that some of those associations have passed through Google's servers before reaching Bing. The point is that Google is not creating these associations. They're algorithmically picking them up from others, just as Bing is doing.
There are many sites on the internet that generate a set of links based on form data. Google is one of many in that respect. This technique is effective in gathering search information on this "deep web". Special-casing Google positively or negatively is the wrong approach here.