I wrote an article referencing the whole barefoot running issue (as well as other issues related to footwear).
The one issue I have with barefoot running and the Vibram shoes is that people think that switching to these types of methods will lead to less injuries and performance improvements automatically. I see people wearing the Vibram’s for all their running, on all surfaces. Of course, their running technique still looks horrible, even if they are not heel striking. I know sprint athletes who have tried the Vibram shoes for some of their workouts and, inevitable, it leads to heel bruises, plantar fasciitis, turf toe, shin splints and other problems because they thought the Vibram would simply replace their other shoes.
One athlete took his Vibram’s trail running and almost had his toe ripped off when he caught it on an exposed tree root. Not a good risk-to-benefit ratio.
So, be careful how you assess and apply the results of these studies. As always, common sense should prevail.