There are 2 ways I see it happening. Either A:They have been pouring almost all their time & ability into making this expansion really good, so the best they could give us to hold us over is rehashed content from before, so we would have something to do, but it wouldn't take them to much time to give it to us, and wouldn't detract from the real work. Or B:They have ran out of ideas, and are giving us rehashed content to reflect that, so when the Expansion pops up & is like all other content, we aren't all to disappointed.
If its A, then I understand it & would actually be happy so long as its good, its like when I make Pot Roast, it takes about 11 hours to make, but its badass in the end, if I get hungry before its done though I eat some left overs in the fridge, sure they may not be as good as when 1st cooked, but they aren't meant to be, they are just meant to hold me over till my Pot Roast is done, then I can really eat the good food!