A few bugs don't stop Awakening from being an expansion every fan of Dragon Age Origins should want.
If you didn't really enjoy Origins or spend much time on it, then you likely aren't interested in this expansion. If you did, the major concerns are probably more about making sure your character imports. It will. but even if you don't import, the game will start you out with a custom level 18 warden. Regardless, you'll have an easy time getting into it, as long as you are familiar with the original game.
The story is centralized around rebuilding the number of Grey Wardens in the fortress Vigil's Keep. The darkspawn aren't leaving like they should and you're tasked with figuring out why. You'll spend your time completing quest and killing darkspawn. Its hard to say more without spoiling some of the plot. Lets just say you'll have plenty decisions to make as the new Warden Commander in Armaranthine.
There are a few issues that one needs to be aware of. First off, there are several bugs. Some will prevent you from completing optional quests, including quest to gain the favor of some team members. Its slightly annoying but I never found a glitch the broke the game. Hopefully they'll all get fixed eventually, but for now they exist and you'll probably hit at least one. Another issues is that there are no more conversations with team-members at camp. This gets rid of a lot of their depth and it feel like you just have to luck into them telling you some about themselves. Its a missed opportunity too, since there are plenty of new faces.
Even with its problems, Awakenings is a fun and lengthy expansion on an already great game. There is some great story, some nice characters, some cool fights, and plenty of choices. Overall it is exactly what a good Bioware RPG should have and exactly what fans will want. If you have Dragon Age Origins and liked it, get Awakening! Its that simple.