When I first came across this thread, I wasn't planning on joining only because there are several popular "charities" that I will not support because I feel they do more harm than good and I didn't want to have to choose between going back on my word or acting against my principles in the event that one of them was chosen as the Bitcoin100's first recipient.

I see now that I needn't have worried.

Not only do I feel comfortable donating to the charities mentioned by Phinnaeus (at least the ones that I've seen - I'll confess that I haven't read every reply in this thread), the Bitcoin100 seems likely to gravitate toward the most worthwhile of causes.

That being said, I've sent 3 BTC to the vanity donation address - one for each of my for-profit bitcoin ventures (at the moment, that's BitBrew, The Bitcoin List, and Unofficial BTC). I also pledge to send 1 additional BTC from each active, for-profit bitcoin venture I'm personally responsible for to each charity that gets my vote.