Barefoot Running

So I have decided to try Barefoot Running. I have been enjoying getting fit and running around 4-5km 4 times a week, so I thought I would take on an extra interest/challenge. When I was in the U.S. I bought some Merrell shoes from REI so it was relatively cheap for me to get into too. Barefoot shoes have no padding and you do have to change your running style, so I am easing into it slowly as I don't want any injuries. However, I can already feel the change in muscle use (read pain) from only one walk/run. It is quite exciting though, as I love the concept!!!