These murmurs have become louder over the past week, and in this week's issue of Science, the authors of the study published last week have conceded that the specimen's true age and locality are not known, as the specimen was in fact bought from a dealer.
Let's be clear: testing the authenticity of a fossil is incredibly difficult, as hoaxers have got incredibly adept at creating convincing fakes. Never mind that Archaeraptor, the most prominent faked fossil of recent times, was 88 separate slabs glued together with builder's grout. This apparent bodging could only be revealed with a high resolution CT scan, not normally available to most researchers. The Anchiornis team seem to have done their best to guarantee the fossil, noting that X-ray and CT show nothing suspicious.
If the specimen is revealed to be fake, however, I will be very disappointed. Not because of the lack of specimens like this, because there is a veritable flood of these things from China. It will be because every time this happens, it undermines our credibility. There is an understandable desire to hype these things up in the media, but if the media keep getting stung by hyping fossils that subsequently turn out to be fake, then I expect that paleontology stories as a whole will get sidelined.
Thankfully the flood of these fossils has meant that we are braced for impact if just one turns out to be fake. If is fake, however, then it will be the most prominent fossil for a long time to have been published at the highest level. Remember that Archaeoraptor never got as far as even being published in a peer reviewed journal, yet it is routinely used as a stick to beat paleontology with by the you-know-whos, many years after it was diligently exposed.
So let's hope that the additional tests that the research group are doing on the fossil throw up nothing untoward. I would say that it doesn't have that far to fall if dethroned, but you can never tell what the impact of bad PR stories can be.