I’ve used Xfce as a window manager for almost four years now. It does everything I want: flexible numbers of virtual desktops, no icons on the root window, customizable root menus, adaptable mouse behavior, and vitally important window management features such as window shading and window hiding.
I couldn’t do my work without it, and I keep finding new features and enhancements (xfce4-verve is wonderful). Thank you to all of the Xfce developers, documenters, testers, and other contributors!
I discovered Xfce when I was trying out gentoo Linux. I couldn't seem to get XWindows working (I was trying to use Gnome). Finally, I got twm to come up somehow (I had no idea what that was at the time). Then I decided that if twm worked, maybe something simpler than Gnome might also work. I researched the options, found XFCE, tried it, and it worked! I currently see no reason to ever try anything more complicated!
XFCE is cool in deed, I have been using it for a while and is definitely one of the lightest-yet-usable Linux WM (icewm is good too). Yet after using it a lot, I have even started to be so glad when I found solutions for things like verve or the kb-switch plugin and so on...
But the thing is... I realised I started to become happy about things that are natural in other window managers, is that normal?
Chromatic, I hardly use window shading/hiding. Instead, what I really appreciate is 'windows snapping'. When moving or resizing windows, the borders act 'magnetic', they are automatically drawn to screen border or other windows. What made me smile is that apparently, each has his own favorite features. Xfce's window manager is quite complete that way.
@Sorin: one of the main features is a piece of code deep within Xfce that makes you happy :-)
Just for fun, I "framed" our friendly XFCE mouse in a blog post about AIM on Gentoo...