[unp3rs0n]

Let's say tomorrow DDG is the search engine with the largest market share. Then Bing would be getting all the clickstream data from DDG. I hope you do realize that this "algorithm" is not Google specific. Its just a novel ranking technique that incorporates a human user feedback loop and is a pretty well known technique in the information retrieval field.

[moultano]

It would be equally unethical to be copying DDG's results in this fashion.

[nostrademons]

Highly ironic, though, as DDG uses Yahoo as a backend, which uses Bing, which uses Google, which would use...DDG? I think there's a cycle in that list somewhere...

[seanos]

Equally unethical sure (x=y), but differing opinions on whether that (x) is ethical or unethical. Personally, I see nothing wrong with it.