It's fully active. But some features require a post count to be achieved.
A couple of months ago, we cut down some features, and profile editing was one of them. The same applies to using PM's, etc. The reason, essentially, was spamming using profile fields, especially the 'home page' feature. Normally, it would activate those features after 15 posts, that being low enough that it doesn't take genuine people long to get there, but high enough that spammers either usually either don't bother or have been spotted sand ejected by then.
But as a long-standing (if inactive
) member, and an old friend, I've turned it on manually now.
There's a section in the
FAQ about it. We do try to keep it up-to-date, but especially if trying something on a test basis, it might not be shown in there.