Medium’s open for all, just sign in with your Twitter account and you can use Ev William’s latest publishing platform. It’s good, very good in fact, and focused on content rather than anything else. Content first, as it is and were. I want to like Medium, and I do on many levels.
But Medium’s a bad idea for you. It’s a locked canister for your content, a window to the web that might just as well be gone in a year. I don’t doubt that, should Medium go south, there’ll be export options, and the open source community will make sure that you can import your content to other platforms, but all your links will be dead, even if your content isn’t.
That’s not all. When you put your words on Medium, when you move your blog to Google+ or Facebook, then you’re effectively building their brands respectively, limiting and sidelining yourself. Tumblr, Blogger and WordPress.com have all solved this problem. You can connect your own domain to these services, and thus should you wish (or be forced) to move your content elsewhere you’ll be able to move it all.
With Medium, not so much, not at its present state.
Don’t ever rely solely on a service where you can’t move your content, and keep your domain and links, to another platform. In other words, putting your well-thought words of wisdom on Medium, Google+ or Facebook is a bad idea.
Unless you don’t give a shit about what you do, and what you publish online, of course. Then by all means, go for it. And by all means use Medium, it’s the best alternative out there, of the bad ones that is.