I got an email from somewhere advocating five reasons to run in a barefoot style foot contraption (I can't bring myself to call it a shoe or foot glove). Here are five reasons not to:
You are chubby
You run on pavement and asphalt from your house
You run on singletrack or off-road
You pronate or supinate
You did not grow up running barefoot to get to school or away from hungry lions and blood-drinking llamas
That is really six reasons but you can combine two or three of them into one super-reason.
Professionally I see way more runners becoming injured running in these things than those getting some sort of benefit. The injured ones then frequently blame the injury on something not the fault of the shoe. Don't believe the hype. If you want to run barefoot do it for short distances on the beach or soft soccer field. Leave the rest to people who are shaped much differently than 80% of you.