That is because that is not set up as a global var i dont believe.  The realname or nickname are very limited in use once they have been recorded.  The username is a global var but the nick or real name is not.  That is why it does not work for you.. It would take a code mod to get the value from what i have seen in the code. 

oxwall shows username in many places, such as title of page after SEO.

The username always be unreadable, no actual meaning.  Showing it in title of pages could be good for SEO ????

Also the username should be confidential because it is part of login information.

This issue and the avatar issue have been bothering me all the time!

Haaa.....

What should I do with them? Waiting?

The username is not as private as you may think, its in the url if you hold the mouse on almost anything the user does, the username is part of that url in the lower left hand corner.  So yes it is not front page but it is not hidden either. 

Placing the Nick or realname in seo is a conflict of almost every privacy statment i have ever seen.  I would not recommend it, certainly not without user approval first. 

Basically now that the SEO is out, youll probably have to wait for someone to do a plugin which will do what you want. So it will take time. 

Ok, I will wait for a plugin....

I my site, a photographer's site, the nickname is what people want others to know themselves instead of username. Such as one's username may like "woo2099", the nickname may like "Commercial Photographer".

 

More than one year has passed.........