I would however refuse to donate to organisations such as Monsanto or the RIAA and for this reason alone simply cannot say "I pledge 1 BTC to any charity/organisation which adds a Bitcoin donation option".
Neither Monsanto nor the RIAA are non-profit organizations.
True that. I was just giving extreme examples. Basically, I'm happy for my pledged bitcoins to go practically anyway as a promotion of Bitcoin itself but even with a quantifier of "charitable organisation" or "non-profit organisation" I simply cannot say that "I will donate to anyone".
What I can do is send 99 BTC (I've sent 1 already) to the Bitcoin100 with the understanding that they (Phinnaeus Gage and/or those he appoints) will give me 3 days notice by e-mail of any organisation they want to fund so I have a short window to veto for my funds if necessary. I'll probably get back a positive response quickly enough but if I don't respond to the e-mail within 3 days then the funds can be used as needed. This would provide some liquidity which would help Bitcoin100 support charitable organisations with short notice.
PM me if you're interested Phinnaeus.