First I agree with all the reviewers to get fitted in the store.  The salesman got it right the first time but my friend went through 3 sizes before finding the right one.

I just came in from my first run and I followed the reviewers and bloggers advice about starting small to avoid injury.  I ran a total of a mile at a moderate pace and my calves are absolutely screaming at me.  You get an insane strength and conditioning workout with these shoes.  When you run in regular shoes your toes mostly stay together, but with the VFFs your toes spread out.  You are using muscles in ways that many of us never have before.

I only ran through the neighborhood but my favorite part was running through a trail in the woods.  The ground was nice and soft and I had excellent traction.  It was an absolute blast!  I'll be using these shoes mostly for conditioning a few days a week.  I don't plan on making the switch to barefoot running ever but its a nice and fun substitute to change the pace a bit.

The only drawback to these shoes is they are just flat out weird looking.  I doubt I'll be wearing them much past running and hiking although they are incredibly comfortable.  I highly recommend them but poke around online on the blogs and reviews for barefoot running.  Great advice out there and if you are still interested pickup a pair.