Don't they contribute little to begin with anyway? I remember there was a bit of mudslinging last year and the hot topic was that Microsoft contributed more code to Linux than Canonical did. While I think they've done great things for the overall landscape - I don't particularly like the direction they've been going since Unity. I'm not saying that it's the wrong thing for everyone everywhere. What I don't like, in particular, is that it feels like they're closing off something that wasn't meant to be. Unfortunate as it is, I hope they continue to remain viable - as they are a stepping stone off of the Microsoft and Apple platforms.