That is very bad example. The youtube results are relevant to the query. In bing the results were not relevant and is skewed against the competitors.
Also google is trying to make the results page more rich by including images and video results. I can't believe that you find it sinister and equivalent to bing's dirty trick.
Modifying pagerank to benefit your own site is on par with what microsoft does in my book, we simply disagree on that.
Both Microsoft and Google should let their algorithms make up the search pages, not their marketing department. Any kind of preferential treatment for their own content is bad. How bad is just a matter of degree.
The google bit was only a sample, similar things have happened with content related to google books, wikipedia (also when it wasn't the best resource on the web for that theme) and so on.
Search should be clean. People trust that you don't meddle with the results.
Google does the same thing by the way.