Every Deviant on Deviant Art should have their on wall on their profile (wall as in like facebook wall)! Kinda Like a Journal but people can post it on other profiles. I hope deviant art can use this sometime in the future!
The focus here is on the artwork. There are already ways to interact without this becoming Facebook.
Think of it this way. If I want to video chat with someone, I use skype. If I want to post my artwork in an art community I use DA. If I want to social network and post stuff on a wall, I use FB. But they do not need to become more like the other, because that destroys what it is good at.
As `miontre said we have comments also if you are premium member you can install shoutbox widget. I would not like another "Thanks for the favorite" spam section.