I would just like to add something. Even though being knocked unconscious for a couple of days seems like a perfectly reasonable result of being taken out, I feel very strongly that the player should not miss any game time as a result of being taken out. In other words, the story should pick up 2 days later when the player character wakes up, or at least there should not be a full scene where the player is unable to do anything. This may have been taken for granted, or someone may have already mentioned this, but I think it's important.
Also, I think it is important to stress to players (especially new ones) that loosing a combat (by concession or being taken-out) in a FATE game is not a bad thing, it just changes the direction of the story. I think we are all so trained from other games (board, video, card, etc.) that loosing is bad, that we sometimes forget that this is a game based around story, not around rolling a bigger number than the opponent. Speaking from personal experience, I used to hate taking consequences and would never concede, because I had it ingrained in my mind that loosing was an undesirable outcome. But heck, look at Luke at the end of Empire; the guy lost his hand, his lightsaber, found out his father was one of the the most evil people in the galaxy, and his best friend was frozen in carbonite, but the story goes on. So if you have a player who is squeamish about concession and consequences, I would point them to movies and/or books. Heroes loose conflicts all the time, bit its all part of a larger story.
It got a bit long-winded towards the end there but hopefully this was helpful in some way.