Of course it will be a sequel! But only for the people willing to dig deep enough. Or, like the producers said: "We don't want to slap new players with Kotor and TSL stuff around the ears."
To link this to WoW:
-Everyone who remember Warcraft 3 knows about the famed scene in which Arthas succeeds his father.
-The blood trails and rose leaves that were in this seen can still be seen in the throne room of WoW. Amazing detail.
And since we will visit Manaan, Korriban I have NO doubt that several quests that would seem to be 'normal lore' for new players would turn out to be exciting links to the Kotor and TSL stories for 'us' veterans.