Firefox Faster than Internet Explorer

There's little doubt that Mozilla Firefox is a better browser than Microsoft Internet Explorer. It is easy to see how the tabbed browsing in Firefox make your life easier, as well its simplicity and better usability.
One thing that I wasn't sure of, though, was that Firefox is faster. Browsing speed can mean several different things, such as download time, how quickly the page is rendered, and so on. It is also quite difficult to quantify. But at least in one respect, Firefox is indeed much faster - scrolling. I've noticed that Internet Explorer seems to be quite sluggish when scrolling through a long page, so I tried to time just how sluggish is it. I opened a page containing about 190kb of text¹, held the "page down" key pressed, and measured how long it took for the browser to scroll through the whole document². The results were dramatic:

• Internet Explorer - 40 seconds
• Firefox - 3 seconds

So at least in one respect, Firefox is indeed much faster than Internet Explorer. Granted, on a faster computer the sluggishness of Internet Explorer may be less noticeable, but still it shows that something in its rendering engine scales very poorly.
¹ This is the page I used.
² Measured on a 800Mhz Pentium III.