The specimen is described in the December 2nd issue of Science Magazine. The hot issue that I see arising from this specimen is the cladogram produced from its study. First of all, for those of you who don't know, a cladogram is the graphical depiction of a hypothetical evolutionary tree. The evolution of birds has been in hot debate for quite a while, and everybody who studies the topic produces a cladogram different from everybody elses. Because an analysis can produce more than one cladogram that is equally likely to be correct given the data, researchers make consensus trees in which uncertain areas are collapsed to a polytomy. The tree that the analysis of the new archaeopteryx produced is a consensus of 288 equally likely trees. As a consiquence, it shows that birds are not monophyletic; meaning that they arose twice. One lineage produced Archaeopteryx and another produced Confuciusornis. Even here there are multiple ways of interpreting the data. It could be that dinosaurs developed wings then re-evolved large body size and a secondarily flightless habit, only to re-evolve flight in some small bodied forms; or that "flight" (quotation marks because many argue that it was a terrible flier) is not the ancestral condition for the whole lineage; or that the authors are wrong in placing birds into two separate groups.
It worries me that the authors didn't include any members of crown group aves. In this sort of analyis, had they included modern birds, all the birds might have clumped together rather than being seperate. It all depends on who you include in your analysis; more so than how complete your fossils are. Don't get me wrong, an incomplete fossil creates alot of uncertainty, but exclusion of taxa creates more.
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