I've never quite liked MMO's...
And personally IMO they ruin the settings. Constant renew of content hurts something that's been already established. WoW is an mmo whose story has incredible amounts of text, yet holes everywhere.
KOTOR II TSL did the best that it could to fix the cliche-storm of KOTOR 1 & adds some certain degree of sense to the journey that the player went in the previous game.
It's writing it's superb, it does the job for both titles.
MMO's are in constant demand of renewed content. So IMO it will only hurt the franchise in terms of storyline.
The game itself I don't care if it's going to suck or if it will be amazing, I just can't get myself into MMO's.
They're just not my thing.