Interesting article about whether Aurornis xui is a bird, a dinosaur or a fake:

During the Jurassic period, between about 200 million and 145 million years ago, some meat-eating dinosaurs began evolving birdlike skeletons and sprouting feathers on their bodies. One group of these creatures eventually split off to become birds, although researchers have long debated which one it was and when it actually happened. Now, a team of scientists claims to have found the earliest known bird, a discovery that could finally put these questions to rest. But critics question whether it really is a bird, and some are not entirely convinced that it’s an authentic specimen.

Read more: http://www.brisbanetimes.com.au/technology/sci-tech/worlds-first-bird-scientists-in-a-flap-over-fossil-20130603-2nl2c.html#ixzz2V8uHRtrH

Obviously it is important to determine whether it is a fake.

The discussion of whether it is a bird or a dinosaur is straight clumpery and is not that important. http://xkcd.com/1211/

The current best family tree showing Birds, Archaeopteryx, Troodon and Dromaeosours is this one. It puts Aurornis xui very close to the line of descent of birds. Interestingly, Xiaotinga http://en.wikipedia.org/wiki/File:Xiaotingia_fossil.jpg is placed even closer.