I think any nearly complete fossil that is 47-million years old is a valuable find. However, I also think it overstates the case to claim this is the "missing link" or the "holy grail of evolution." This is clearly a useful find in documenting the history of primate evolution. So in that sense it may give us valuable information about human evolution. The importance of that information remains to be seen.
Frankly, I can't help be skeptical when a find that has been studied in secret for about two years is suddenly announced with all this hype just before a History Channel special about the find. This reminds me of the much touted discovery of what was supposed to have been Jesus' family crypt a while back.
You might want to read P.Z. Myers take on all this. He has a new comment in today's Pharyngula blog.
Oh, I'm sure the fossil is legitimate. I am, however, very upset with the media circus surrounding it. Science isnt' a popularity contests. New discoveries don't rewrite science books. Point of fact, if someone had asked me what the last link between Lemurs and monkeys was, it'd have been something very similar to this.
It's just that it's unhelpful to keep a discovery in secret like this, so that a guy can make a media circus out of it, before allowing his peers to review his findings. It's bad science all around as far as that goes.
I think the only viable reason for keeping this new found fossil a secret for two years while studying it would be to make certain of what they had and not jump to any conclusions. It would be very damning to the scientific community to come out right away and say they found the missing link only to discover later that it was something else entirely. If that had happened I think it would be reasonable to assume that the religious community would have jumped all over it saying how science had failed again at disproving creationism.
But they could have released information about the fossil without calling it the Holy Grail or all that nonsense. If they've had it for two years thats plenty of time for a thorough analysis and then submit a paper that contains JUST FACTS. THEY are the ones pushing all the hype. A fossil of that quality would have merited a small mention in pretty much any paleontological journal as a "OMG PRETTY!" spot without having to make any claims about it's relevance to human evolution or anything.
But no. Media circus instead of the usual pathway of submitting a paper, the journal sends out sumarries to major newspapers and the papers follow up the ones they care about.
It seems not everyone is convinced this fossil is in the human line. I hope they don't have to announce that they have erred, it gives the creationists too much ammo. It's very cool anyway. But there is no such thing as 'the missing link' for gods' sake, the missing link to what? Everything is a link to something unless it had no descendants. This idea is sooo nineteenth century.