People have been wanting to bring a friend along in either Fallout or Elder Scrolls for a long time but it has always been a single player game. Personally, I've always thought they should have the option of being a co-op game. These are only rumors so far, I think a wait-and-see attitude is the best option, especially for fans.
Now, Elder Scrolls is way overdue for a sequel and I can only surmise it is because of the success of ESO. I have been playing ESO every night for well over a year now. I gave it a chance and I do enjoy it, but it just doesn't have the single player feel to it, unfortunately. Still, it is a lot of fun to play, especially with friends. If you are playing it single player style, it isn't that fun and quite difficult at times.