MSN has just recently passed yahoo for the #2 largest search engine. MSN has lots of funding just as google does. Each will keep updating, I think MSN has a long ways to go to reach Google's efficiency.
As MSN is not good as google in indexing the sites. As Google is the best search engine, and it has many users all over the world than other search engines. As your site is indexing on the google then you must do not go to other search engines.
Google rules the roost! I depend on Google for relevant info and updates. I think Google search results are updated and accurate. I prefer Google to any other search engines.
The fact is known that Google is much stronger and more active than MSN though it would be hard to say exactly how and compare them on a common platform.