They have released a closed source git/github client already. And now a closed source text editor. I find it really hypocritical from a company that loves reminding us that they use free software, even in closed projects. I’m just saying that they rarely give back to the community. Of course they “give” free repos to open source projects. Why? Because that’s how they bring new members to the website, including members that will pay to host closed projects.
I strongly suggest github to release atom under GPL.