Interesting hearing about how they want to tackle the Microsoft ecosystem.
As someone who spent years in that ecosystem and recently left it for OSS, I'll be curious to see what kind of success they see and who they are targeting.
Phil Haack is one of the people who recently joined Github from MS developer tools division, with the aim to make the github experience better for those same devs.
I'm pretty sure the other person is Paul Betts. They are working on Github for Windows (i.e. a Windows version of what they've done with Github for Mac).
Related, I never really got the point of "Github for mac". Do we need a fat-client app when we already have a first-rate web app? What does it do/enable/make easy that github the website doesn't? A Mac or PC isn't a tiny phone screen with no keyboard, where native apps are more usable than websites.
I use TortoiseGit as well for the rest of the github experience, since I'm not a git master and I can pretend it's SVN with pull requests.
As someone who spent years in that ecosystem and recently left it for OSS, I'll be curious to see what kind of success they see and who they are targeting.