Microsoft will be issuing an out of band patch for Internet Explorer for all of their operating systems and all versions (5 through 8 beta). Read more here. Basically, IE is really unsafe (no, duh) and you shouldn't be using it.
I mean it. This is my day job...
Really now, practice safe net:
These are all alternatives and I recommend most of them for your daily browsing needs. Unless you really need IE, I suggest switching and switching for good.