Medium, the blogging platform developed by Twitter co-founders Biz Stone and Evan Williams last year, is finally opening its doors to the public – but there are still a handful of restrictions.

For the uninitiated, Medium is a blogging platform that is closely tied to users’ Twitter accounts. It allows users to publish longer-form thoughts, complete with images, links, etc. Medium allows users to “recommend” posts that they like, and trending posts are shown to users on a homepage. Medium also features “collections” that users can follow and contribute to – for instance “Best Thing I Found on the Internet Today” and “Comedy Corner.”

“Not too big, not too small” is the platform’s slogan.

If you head on over to Medium.com, you’ll see a prompt at the bottom left-hand corner that says “sign up via Twitter.” Once you do that and confirm access through your Twitter account, the green button will change to say “request writing access.” From there, you’re just an email confirmation away from posting on Medium.

Why does Medium want you to have a confirmed email address?

“Why, you ask? Connecting with other readers and writers is a big part of the Medium experience. We’ll email you about interactions with other people on Medium. We also regularly invite users who read to write on Medium. We’ll email you when you’re invited to write,” says Medium.

Before today, access to write on Medium required an invite. The Next Web was tipped off to the open registration in a weekly email to users.

About those caveats…

You can only post to Medium if you’re on Chrome, Firefox, or Safari. Sorry IE users. Also, mobile creation is a no-go, for now.

“Creation is not yet available on mobile devices, so even if you can post on the web, you won’t be able to post on your mobile device. We’re working on this,” says Medium.

Anyway, go check it out.