You can get themes as well...which makes it nicer to look at and it's not so boring as ie.
Tabbed browsing is so good, once you get it, you realise how annoying having loads of windows on your taskbar was.
there are also extensions you can download. Like at the bottom of my browser window, I've got a local weather forecast for today, and the next two days, and a little control bar for itunes (you can set it for every music player i've ever heard of) so i don't have to switch screens to control my music.
so basically there are loads of extras that IE doesn't have.