Two things to report.
First, I've noticed that a "clear link" (not visible in most web browsers) labeled RSS is included in the source code of MSN Search Beta results pages. Look for it near the end of the page code. I also have a screen shot here. RSS and MSN Web Search? Very interesting!
UPDATE: Greg Linden has posted an example of how to access MSN Beta search results delivered as an RSS feed. A new current awareness tool. Thanks Greg!