I use KDE since 2004 (do not remember which version it was). Lot of things changed during that time. But not my X11 session use.
Since beginning of my Linux use (in 2000) I use one set of virtual desktop. Their amount changes from time to time but there are always at least 4 of them (six at the moment):
1. “work area” — terminal, gvim (few copies of each)
2. “web area” — here I have web browser (now it is chromium, was firefox, galeon in past)
3. “mail/news are” — mail/news reader (kontact with kmail/knode, was sylpheed-claws at some time)
4. “misc area” — here I run software which do not fit to first three
Terminal application changes from time to time. First it was GNOME-Terminal from GNOME 1.4, then Konsole, xterm, uxterm, rxvt-unicode, eterm and few others but after experimenting with many I stayed with Konsole. It has tabs so allows me to run many sessions in one window. Some of tabs have “screen” attached as this allows me to quickly get another shell in working directory and also easy way to log any output (“tee” sometimes got blocked). With recent KDE 4.x changes I started to using “window grouping” to split tabs related to other tasks from main terminal. This gives me one terminal window on screen with few tabbed windows in it which can have own tabs which can have screen sessions in them. May sounds strange but it works. And I always have screen with “irssi” running in it (on local or remote machine).
As editor I use gVim mostly. I kind of mastered it and do not feel good in Kate, Eclipse, JEdit or other “so called normal” editor. Never tried Emacs but do not plan to.
During UDS-M when I told that I am using MPlayer for all videos reaction was interesting. I got list of modern video players (mostly GStreamer based ones) which I should switch to. But I really do not see a need for it. MPlayer maybe is pain in the ass sometimes but it plays everything I have, adds subtitles in a way which I like, has controls on keyboard which I remember and [allows me to seek instead of fast forwarding](http://marcin.juszkiewicz.com.pl/2010/06/30/seeking-or-fast-forwarding/) during watching film. Ok, on devices like BeagleBoard I probably can get better results with GStreamer based apps but thats due to codecs which can use DSP.
I never liked Konqueror — always used Gecko based browser. It was Galeon 1.x in past, Phoenix/Firebird/Firefox later, Chromium now. Tried Opera (UI never managed to integrate with look&feel of my desktop) and few other browsers. Chromium is nice but has some drawbacks. Maybe some will be fixed/changed.
Even removable storage I most of time handle with “pmount” command. It works fine for me and I do not like to have all my pendrives/memory cards/etc to be auto mounted. How will I notice which is which in situation when I plug 2 same ones… And UUIDs or filesystem labels are not solution probably. But maybe I will change that in next months.
But back to desktops. KDE 4 has widgets on desktops, activities and few other buzz words. I do not use them. Ok, panel has few widgets integrated but it is still panel. I simply do not see a use case on my desktop for most of widgets. Even after trying them.
So if someone wonder why I do not use something which “everyone is using” then I hope that I gave an answer.