"Today we’re announcing that you can donate Bitcoins to homeless people" is the worst sentence I've read on the Internet today.
One cool thing that the block chain enables is the possibility of publicly transparent accounting. This should enable charities to show that they are honest and give some guaranteed percentage of their funds to those that they are helping. I think that more people are willing to donate when they can directly see their money making a difference as opposed to it just falling into some giant funding bucket.
Ha - we're now really living in some kind of cyberpunk future where crypto-currency can help the homeless through the internet!