One of the main reasons I don’t use Firefox and still use Internet Explorer has to do with how Firefox deals with drop down lists in web pages. Drop down lists are often used on web forums to navigate to different sub forums.
Here you can see in Internet Explorer that items above and below the currently selected item are displayed meaning you’re less likely to have to to scroll up and down if what you want is a few items down on the list.
In Firefox once you have moved to the middle of the list the currently selected item is at the bottom forcing you so scroll down to select lower items.
Since I spend a fair amount of my time on the Internet reading web forums and I use these drop down lists as my primary method of navigation though web forums this small difference really annoys me.
The other small thing I don’t like about Firefox is that the bookmark menu will close if I middle click to open the page in a new tab. In Internet Explorer the menu stays open when middle clicking allowing me to open many pages quickly. While I can do this in Firefox by opening the bookmarks side bar, I don’t like doing that as much since the side bar is a bit cluttered and I have to manually close it once I’m done opening pages.
So those are the admittedly silly reasons I still use IE, if it weren’t for those minor dislikes I would be using Firefox as it is an overall better browser.
Update July 1st, 2009
Firefox 3.5 was just released yesterday, and while it’s fairly awesome I’m still sticking with Internet Explorer for the reasons mentioned above. Also as strange as it may sound to most, I actually (mostly) like the layout of the interface in Internet Explorer.
Update March 8th, 2010
I’m giving Google’s Chrome browser a try as my preferred secondary browser now that AdBlock is available for it. Also I’m trying out LastPass as a replacement for Ai Roboform since it supports IE, Firefox, and Chrome since Roboform only supports IE and Firefox also because Roboform caused some minor graphical corruption in IE’s tab bar when it was setup to work properly with Firefox.
So far my only major complaint with LastPass is that it has crashed a few times in Chrome.
Unfortunately Chrome has the same favorites menu and drop down list behavior as Firefox that I mentioned which it preventing me from using it as my main browser.