Ed Yong has a nice discussion of a recent paper about a feathered dinosaur over at his blog (Not Exactly Rocket Science –Tianyulong – a fuzzy dinosaur that makes the origin of feathers fuzzier). The neat thing with this fossil is that it suggests that the evolution of feathers might have been a stepwise process, and indeed their origins may have predated the the last common ancestor of the Saurischian and Ornithiscian dinosaurs (see figure below).
One more example of how we are gradually accumulating more and more supporting evidence for evolutionary explanations of the origins of birds. You can clearly see the feathery “filamentous integumentary structures” in the fossil:
Primary citation: Zheng, X., You, H., Xu, X., & Dong, Z. (2009). An Early Cretaceous heterodontosaurid dinosaur with filamentous integumentary structures Nature, 458 (7236), 333-336 DOI: 10.1038/nature07856