This trickle of temporary content called the Living Story is a failure IMO.
I do not believe I will buy a GW2:xpac if it were released with the base game as it stands today.
ANET can use the LS vehicle to progress the game by creating new permanent content every quarter or so. If I were them, I'd have used gemstore to sell content updates time to time like GW bonus mission pack. I'd open up an area in far shiverpeaks, add events and temporary dungeon access but, sell the permanent dungeon access for 400 gems instead of selling fluffy hats for the same price. I know there are people who like fluffy hats but, I'd rather pay for the content and not the fluff.