That's PC only, mate. The 360 version was just released, so let's re-evaluate that number again in a couple of months.
Yes, 1,3 million units sold in NA is considered a failure by BioWare's/EA's standards, since they are the one who aimed to sell 10 million+ units. Well, they failed.
If something like Skyrim can sell 10 million units, then BioWare (self-proclaimed "best RPG developer and story-tellers out there) certainly must reach that target too, no?
Except, BioWare doesn't get it. They're stuck in their old ways and that's why they continue to become more and more irrelevant.