Paul, love the post, it's something I agree with 100%, as I'm sure you'd imagine. I'll just point out a couple landmines I hope you'll avoid in terms of what I imagine the reaction will be, as we stepped on them a few times with Eve.
The first is you spend a lot of time correctly pointing out the things that are wrong with the way things work today. This gets people who are invested in the way things work today defensive. They'll rightly point out that Dark doesn't fully exist yet, so you can't defend your claims, and they'll point to things like Eve to say you're next in a long line of failed projects, and they won't be wrong.
The second thing I think you need to answer in your piece is this, because it's going to be one of the first things people bring up. You talk about how Dark will solve a bunch of problems if you do your work in the Dark ecosystem. That's great, but that raises the specter of lockin. You've gotta answer questions like: how does Dark fit into my existing ecosystem, is it open source, and is it free.
Third, the article is a bit of a tease. I think that's what you're going for, so that's okay, but it does leave one without a sense of really understanding what Dark is. Without something to show, that's difficult to overcome. So my questions for you is, what do you hope to get out of this post? Is it for people to join your mailing list and follow you on Twitter? Is it to just get some buzz going? Is it just a kind of manifesto?
All in all, a great post, I think it will get some buzz on HN and other outlets, but I warn you to be prepared for some incredulous bickering that comes with the territory.