Only thing that matters in Skyrim is the world they created. Quests are horrible. So if BethSoft shares their resources with guys who are making this, it really can't end up worse than Skyrim.
Also, I don't see how will other players ruin your immersion. Skyrim is pretty static game but MMORPGs aren't dynamic either. It's not Warband singleplayer where things happen over time.
Hopefully they'll realize that directional combat is the way to go, I really can't ask for more than that.
It seems they're planning to make a whole continent of Tamriel, I'm pretty sure they'll need every single designer Zenimax Media has under it's command, to finish such demanding task.
Can't be worse than The Old Republic and Diablo 3, that's for sure.