Ecchi, perfect example: My sister uses dialup. At 56k, some microsoft updates take all night to download. She would rather I come pickup her computer once every 3 or 4 months and run the updates as one big pile. The last one she truly did was the one that locked up your system if you didn't complete it. Otherwise, they have turned off the automated updates because they are on dialup.
I would suspect that many dialup (especially AOL) users are in the same boat.
4% of all surfers to findpics are using a version of IE lower than 6.0, which means they are certainly not even up to patched to 18 months or more ago.
The other part of it is Active-X and other "non browser" features of the IE browser. Support for local zones and other issues are where most of the security issues happen. Moving content from "untrusted" (can't run anything local) to "trusted"(can screw you over in an instant) is the goal of all hacks and security exploits. Getting something inside the gates (pun intended) of you system is the key. Most of those things exist because the browser is also the "control panel" and "file viewer" and "search" and all those other things on your PC. (heck, you can open up control panel, and type
http://www.cnn.com in the bar at the top and be surfing). That situation is where almost all of the issues come up with microsoft, the dual nature of their browser.
Firefox and others are not really made to do the same things, so many of the obvious places to look for good security holes are not there to work with.
Alex