Quick update on the new, primitive sauropodomorph Panphagia:
Adam Yates, at his blog Dracovenator, has his own post about this critter with a juicy bit of goss that applies to the old, early dinosaur favorite Eoraptor. Eoraptor is variously considered to be a primitive member of the theropod branch of the saurischian tree. Makes sense, since it's a small bipedal carnivore like all other primitive theropods.
Apparently Panphagia and Eoraptor are so similar that Yates reckons the authors of Panphagia are implying that Eoraptor might actually be a primitive sauropodomorph itself! This would be a mighty cool turn of events, giving us the most primitive of primitive sauropods and a very theropod-like, fully carnivorous one to boot. There's no solid phylogenetic evidence for this yet but it hasn't really been tested for either. Keep an eye on how this shakes out in the future.
Picture of Eoraptor is public domain from Wiki Commons.