Today after a lot of tweaking and making some changes to and from a tutorial on MyBB, ECC now supports logins and registrations with Twitter.
However, there's no obvious way of doing it yet, that is because I have plans for a special welcome box for guests and the plugin that is behind that little box is not playing real well with MyBB GoMobile. I've made a thread on the MyBBGM forums and probably will be asking for a solution on MyBB Hacks where I got the plugin, but for now that's on hold.
Anyway, it works seamlessly. I need to change the username template to something more presentable but for now everything works, it's just not available until I get a solution to that bug.
Next up, Facebook logins and registrations. Yeah man.