Seems like there has been a lot of interest in centuries these days. My guess is that after a nasty winter people are anxious to spend more time on the road, and riding a century is one way to guarantee that you will do exactly that.
There are some good threads going on about recent centuries and/or training for them:
Training For The Almighty Century; a journal
First century ride report
For the rest of us, how's it going? Any road warrior stories to share?
BTW, these threads always seem to attract posters who have to say why bother, why would someone want to do this, can't you just ride and enjoy life, etc etc. If you feel inclined to make these comments, just go away. Post about plans to decorate your Brooks saddle or something.