Executive summary: If you're using Internet Explorer v7 or earlier as your web browser, you should seriously consider switching to Firefox. Even if you're using the new v8 of IE, you're still not going to have as much protection from malware as with FF and the NoScript plugin.
I have been using Firefox as my primary browser for several years, and generally try to avoid Internet Explorer as much as possible. (Sometimes, though, it's not possible - my previous employer only supported IE for all of its Oracle infrastructure.) IE, being the most popular browser in the world - primarily because it is essentially built-in to Microsoft Windows - has been the primary target of cybercriminals for quite a while. Also, I like the fact that Firefox's user community has developed any number of (occasionally) useful plugins for it.
What prompted me to finally write something about Firefox and NoScript (this has been on my to-do list for a while) is the zero-day Adobe exploit that I posted about earlier today. NoScript can protect you from the exploit described in that post.
Finally: At the top I mentioned IE v8, which was released recently. I was hoping that Microsoft would take some steps to improve IE's resistance to malware, and I think they've made some good progress, but I found an article that seems to indicate that IE still has a ways to go. So although I'll continue to evaluate IE v8 on my Vista install as an intellectual exercise, I'll be keeping Firefox (and NoScript) as my favored "surfboard" for the indefinite future.