Cheers KDR! Opera user here too. It's so much better I'm planing to purchase Opera 7.21 (already owning Opera 6). Several more features of Opera no IE user knows about, or even can imagine being there......
* Ctrl+Z! You know what that one does? It's Undo, but no, not just stupid IE text box undo, it actually reopens your accidentally closed pages

until you start using that you won't know how good it is.
* Spatial keyboard navigation. You won't touch the mouse anymore, you won't need it

One can finally traverse the links and forms of a page using the 4 arrow keys, it's instantly became of my favourite features of this browser.
* An old one IE won't ever have : open a link in the background. What do you do seeing a page with lot's of links (i.e. images etc.) you want to visit? Start clicking and hitting back/alt-tab. Well in Opera you can just put them loading in the background, one by one, with a single click, and at the time one starts looking at the first link it's already loaded (Yes this browser IS fast.)
* Best ever email client (called M2). Won't start enumerating features here.
And that's just off the top of my head, if you won't more I'll tell you all

Hope this makes some of you ppl consider trying the latest and greatest.
Cheers,
kfet