This will probably not come as a surprise to many, but my statistics show that Google is the clear leader across the board. Recently I checked some statistics on which search engines are sending traffic to my ittyurl.net site, which has really started to take off. The bottom line:
2. yahoo 1,666
3. aol 76
4. search 64
5. altavista 24
6. msn 12
MSN is at the very bottom, man! My site has long since been submitted to all these search engines, and it has a standard XML Sitemap for them all to consume.
The sitemap is automatically updated at least once a day, and anybody who's got an RPC or other PING mechanism is getting notified of any new content in realtime.
Yahoo is making a showing, but the others are so far behind, it's a JOKE! Google is the clear winner, by a long shot.
You guys want my business? You need to crawl my site(s) and send traffic. It's a pretty simple equation to me! I'm the web site owner and producer, and I have the original content. Your job is to index it. If there wasn't any content to index, there wouldn't be any search engines. Ain't rocket science!
Finally, I leave you with this terrible true story of the Internet Crash of 2007: