The teeth look like a remarkable match, but I'm not a bone person. What do you think C-man?
My first impression is how straight the tooth row on the "4.1-million-year-old Au. anamensis, left" compared with the slightly parabolic tooth row of the "previously discovered teeth of 3.3-million-year-old Au. afarensis, right." Not sure how much of this is the reconstruction. Given the wear on adjacent teeth, the angle of the tooth row can be estimated pretty well though. Also, there may be bone which does not show in the photograph.
Second impression is the slight decrease in size; not sure if this is evolutionary or due to the relative sizes of the different individuals.
To me the teeth themselves look quite similar, but teeth are a real specialty, one which I never studied much.
Tim White has been doing some good research, and adding to our once sparse collection of hominid fossils at an amazing rate. It is tough to judge these things from photographs, but you can bet the folks with the actual bones have been studying them pretty carefully.
It does not take too many mistakes to get you canned in science. Accuracy is very highly prized. I would tend to place a lot of trust in what they have to say.