I also prefer barefoot when possible. I do believe that for a lot of horses, it is a healthier choice. For example, I used to do hunter/jumper shows with Beau, and he would stumble and trip no matter what type of shoe he had. I decided to have his shoes pulled and go barefoot with him; he didn't even have a 'transition' period. He was 100% sound, with riding and everything, from day 1. (Although I did give him a short break where the most I did with him was walking to be safe).
We now live in Erie, PA (NW corner) and I do primarily trail riding with him and he is still going strong. I've had several farriers remark on how strong/thick/tough his hooves are and how great of shape they are in. However.
I also have no problem whatsoever in realizing that it is not by any means a method for every horse. Some horses do need shoes. Some horses that go great barefoot, might also need shod if their workload/terrain is being changed/increased/what have you.
So while I am a barefoot advocate when practical
, it is by no means something that every horse will be okay with or stay sound with.
There are some really awesome barefoot trimmers out there, but for every good one, there are also a LOT who have no clue what they are doing and will inevitably compromise the hoof.
At the same time, the same goes for 'traditional' farriers. There are some really great ones out there who have studied long and hard on how to properly shoe and take care of the hoof, as well as farriers who will just slap a shoe on and call it a day, with no regard to the integrity of the hoof.
I like to look at this on a case-by-case basis and go with whatever the horse seems most comfortable with.
Just my opinion. :)