McFarkus:

There's an adjustment period with them, I'll freely admit that. Theory goes that our feet have been coddled and malformed by regular and athletic shoes, weakening the many muscles of the foot and shaping it to an unnatural stance.

Here's another enthusiast blog about FiveFingers:

http://birthdayshoes.com/

and Mark's Daily Apple on them:

http://www.marksdailyapple.com/even-...its-forget-it/

Compared with wearing a kilt, it's much less nonconformist to switch to Vibrams.