OpenAI forms safety committee as it starts training latest artificial intelligence model

The company has announced a new committee led by CEO Sam Altman to make recommendations on safety and security, following the dissolution of a previous AI safety team. This move aims to better align with the company's goals for beneficial and safe AI systems. Additionally, Sam Altman has committed to philanthropy by signing the Giving Pledge, promising to donate most of his wealth. The Giving Pledge, initiated by Warren Buffett, Bill Gates, and Melinda Frenchgate in 2010, encourages the ultra-rich to contribute to charitable causes.

According to Bloomberg, what is Sam Altman's estimated net worth?

What is the Giving Pledge and who started it?