I agree. They're open source at the moment, and they've been my icon set of choice for some time - I use them in my open source RSS reader, django-yarr, for example. In fact I came to the comments to complain about how there is already an icon set with that name, before I realised it's the same guy.

I understand why they're going for commercial licensing on top of the kickstarter, but it's a real shame if the new icons never make it into the open source project. I'm more than happy to pay for them if I'm using them commercially, but it would have been good if one of their stretch goals had been setting a chunk of money aside to feed the new icons back into the open source version for people to use in their projects.