A number of prestigious people from AI and other fields have signed the open letter, including Stuart Russell, Peter Norvig, Eric Horvitz, Ilya Sutskever, several DeepMind folks, Murray Shanahan, Erik Brynjolfsson, Margaret Boden, Martin Rees, Nick Bostrom, Elon Musk, Stephen Hawking, and others. I'd edit that into the OP.

Also, it's worth noting that the research priorities document cites a number of MIRI's papers.

There is also a discussion of this happening on Hacker News here.

Is the idea to get as many people as possible to sign this? Or do we want to avoid the image of a giant LW puppy jumping up and down while barking loudly, when the matter finally starts getting attention from serious people?

I'm impressed they managed to get the Big Three of the Deep Learning movement (Geoffrey Hinton, Yann LeCun, and Yoshua Bengio). I remember at the 27th Canadian Conference on Artificial Intelligence 2014, I asked Professor Bengio what he thought of the ethics of machine learning, and he asked if I was a reporter. XD

This has appeared in the popular science page "I Fucking Love Science", followed by almost 20 million people on facebook. I think this is extremely good news. Despite the picture and its caption, the article seems to take the matter seriously.

So if an AI were created that had consciousness and sentience, like in the new Chappie movie. Would they advocate killing it?

I didn't see Ray Kurzwiels name on there. I guess he wants AI asap, and figures it's worth the risk.

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