From their site:
OpenAI is a non-profit artificial intelligence research company. Our goal is to advance digital intelligence in the way that is most likely to benefit humanity as a whole, unconstrained by a need to generate financial return.
The money quote is at the end, literally—$1B in committed funding from some of the usual suspects.
With Sam Altman (CEO of YCombinator) talking so much about AI safety and risk over the last 2-3 months, I was so sure that he was working out a deal to fund MIRI. I wonder why they decided to create their own non-profit instead.
Although on second thought, they're aiming for different goals. While MIRI is focused on safety once strong AI occurs, OpenAI is trying to actually speed up the research of strong AI.
Nate Soares says there will be some collaboration between OpenAI and MIRI:
https://intelligence.org/2015/12/11/openai-and-other-news/