Google Blog Search: No keywords on referrals

Does this bug anyone else? It’s possible with referrals from major search engines to get the search keywords that were used to find the page, which helps you to understand why people read your blog. But referrals from the Google Blog Search strip the keywords off.

A referral string from a regular Google search for “tim jarrett” looks like this:

http://www.google.com/search?hl=en&q=%22tim+jarrett%22&btnG=Google+Search

However, if you run the same search against Google Blog Search and click through a result, the referrer just shows what page was targeted:

http://www.google.com/url?sa=D&q=http://www.www.jarretthousenorth.com/

This is annoying for me, because I like to know why Google users find my site interesting. I understand technically why it happens—the redirect page, google.com/url, causes it because it loads in the user’s browser before loading the destination. But why does Google use the redirects on the search results in the first place? Is it to gather click statistics? If so, there are other, less intrusive ways. Or are they doing something else with the redirects, maybe something to do with stopping blog spam?

Some input from Google would be welcomed here.