The Live Search team has a blog post entitled Wikipedia Gets Big which reveals

Check it out:

We realize that often you just need to get a sense of what your query is about. Wikipedia is great for that — you can learn enough from the first paragraph of a Wikipedia article to start you out on the right path.

For Wikipedia results, we now show a good portion of the first paragraph and a few links from the table of contents. You can see more about the topic right there and see what else the article offers.

We hope you learn more, faster with our expanded Wikipedia descriptions. Let us know what you think.

After trying out on a few queries like "rain slick precipice", "wireshark" and "jeremy bentham" I definitely see this as a nice addition to the repertoire of features search engines use to give the right answer directly in the search results page. I've already found this to be an improvement compared to Google's habit of linking to definitions on Answer.com.

The interesting thing to note is just how often Wikipedia actually shows up in the top tier of search results for a diverse set of query terms. If you think this feature has legs why not leave a comment on the Live Search team's blog telling them what you think about it?

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