If you're into character interaction and story development, don't waste your money.
However, my favorite part of Dragon Age (and Bioware RPGs in general) is the interaction between party members. It is pretty much nonexistent in this expansion. The party camp is gone entirely and the keep which serves a similar purpose offers no character interaction except for when one of their uninteresting plots has an event.
There is no romance, no interesting character quests, no differing levels of loyalty (there's none and warm and probably a negative one).
The characters as a whole are uninteresting and underdeveloped. I was really looking forward to interacting with them based on the preview material available but it seems like most of them were just thrown on at the last minute with very little work or thought put into them. The only entertaining one is Oghren who we already know.
Also, you can expect the same "that was it?" feeling at the end as you probably had at the end of the original game.
Overall a huge disappointment for me, especially considering the $35+ price tag.