Don't know if anyone seen this article yet...
Microsoft has urged users to be wary as three newly discovered bugs leave people open to attack while using the net.
http://news.bbc.co.uk/2/hi/technology/4849904.stm
I think its the more reason not to use IE as your default browser, although at the end of the article it says that people who uses the Beta Version of IE7 are safe... but it is a BETA right?