"But as the Arnolds' profile grows, of course, not everyone is a fan of this science of giving, especially since it comes at a cost to the many individuals and local organizations who need direct help now and could benefit from their billions. The answer to the most asked question may not be known for years: Will their plan work?""
I chuckled at this. All of a sudden, people are asking "will it work?", but they never asked the same questions of the charities they regularly donate to.
My guess is they simply haven't heard of it. I left a comment on the article here mentioning GiveWell and existential risks; if you guys want to click the little "recommend" link that would be great. (First you'll have to click "Log In", then "Log In with Facebook", then go through the Facebook popup, then tell WSJ that you want to skip linking your Facebook account to your nonexistent WSJ account. But this should be no problem given the high number of expected lives you are saving, per Bostrom's paper.)
It seems like they've already spent half a billion of their four billion. Do they have enough money? At this rate they'll run out soon.
It looks to me like this foundation is mostly concerned about solving problems in developed countries, and so isn't likely to provide a much benefit as projects like GiveWell which focus on developing countries.
I think there is an interesting difference and tension between two concepts. One is the traditional charity, "giving". The other one is solving problems without optimizing for profit. I feel they are rather different.
http://online.wsj.com/article/SB10001424127887323372504578466992305986654.html
Apparently a hedge fundie made 4 billion and is giving most of it away to what the WSJ describes as a "moneyball" approach to giving.