I was commenting on this poll [1] by Sortvind [2] at deviantART [3] about web browser usage, and want to share my wonderful insight with my readers. 
I use Mozilla Firefox because of the great tab control [4], automation [5], nice bookmarks toolbar, no text aliasing, other add-ons, and general speediness. But it slows down a lot [6] as I leave one window open for days (using Windows’ hibernation function at night); it’ll even lock up and make everything else slow as molasses, as it steals all the CPU cycles and RAM. I did re-install recently, switching from the portable version [7] to the regular Windows installer [8], but to no avail. It surely doesn’t help that I like to keep 20 tabs open.
Firefox was originally supposed to be simple and fast, replacing the slow Mozilla suite [9], but with spell-checking, RSS support, history caching [10], etc. in the core instead of being relegated to add-ons, it’s becoming increasingly heavy-weight. Inefficiencies in the code [11] don’t help either, though changes will mess up the plugins people love, I hear.
Incidentally, there is the same problem of slowness with WordPress [12]; I and many other users have to use caching [13] to stay running during traffic spikes. Though most database-driven websites use caching, it’s particularly necessary due to WordPress’ inefficiencies [14]. And they won’t be going away [15] or else plugins [16] will break. At least we get lots of cool features [17] out of it. 