I have been using IE all the way. I have a beta of 9. I have been using it for a couple of months. Loads fast but still has few bugs they need to iron out. As long as you stick with the automatic updates, you should be fine.
I would be aware of Google and the Chrome regime. You are doubly "profiled", by using the google search engine AND thier browser.
As an experiment, I ran a version of W7 beta for about a year with IE8, no virus checker or spybot crap. Not a problem. As long as one is aware of the sites you are on and what stuff you download, things sould be fine.