It seems like this decision has more to do with consistency and worldwide branding than Microsoft's dislike for the Bing name. There's currently a preview for the
new MSN home page. IMO, it looks quite nice. It also does a much better job of integrating Microsoft's core Bing services. You can even customize the page. It's also Microsoft's main web portal and the default home page on internet explorer. I could see why Microsoft wouldn't want to confuse people by directing them to MSN to access Bing Finance - but not to go to Bing for Bing Finance - because Bing Finance is on MSN but not on Bing... It's much easier to have one consistent brand name. Plus, it helps in parts of the world where the Bing brand isn't as trusted and used. People that use MSN Finance are likely to stay with that brand (even if they don't realize it's still powered by Bing)