Drupal itself is pretty nice to work with, has an active community, and
is easily extended with modules.
I use it for my own little site
It has nice tagging and taxonomy features, and the admin interface is
pleasant. I'm only using a small subset of its features.
Erion: are you in Oshkosh? If so, I suggest we have a "far northern
suburbs" chipy meeting. Y'all are welcome to attend. The closest
station is Linden, on the Purple line ;)