A worm with an unknown goal and and as of yet unknown payload has been making its rounds among the MSN-using crowd. This comes only a day after flaw in Yahoo's webmail could cause infection was patched. It is becoming more and more common to see worms and trojans go after very specific, popular programs, such as instant messengers and web services, to propagate themselves. The "BlackAngel.B" worm makes a cryptic reference to a movie, then attempts to disable various security programs and diagnostic tools to prevent itself from being removed.
It requires user interaction to become infected, but unfortunately the lack of education about net security will probably result in quite a few people getting hit by it. Because it's already been made aware of, most AV suites will probably have it fixed very soon.