Some other random things which might confuse people watching on TV:

• The opposing team is allowed one person to sweep the rock after it passes the tee line (black line intersecting the centre button). You're allowed to sweep your rocks at any time, even if it wasn't moved by your team.
• Also the sweepers use stopwatches to time the throw usually between the tee line and hog line so they have a good estimate about how the weight is on a draw or guard
• A raise is usually hitting a guard of your own colour into the house. Sometimes can be used to takeout the other team's rocks
• The skip doesn't have to throw fourth, some teams have the skip throw third stones while still calling the rest of the shots. That's why when it says the percentage comparison it says "Fourth" instead of "Skip", since they might not be the same person. Not sure if any team is doing that at the Olympics.
• The thirds (or whoever is holding broom for the fourth's shots) have to decide who is shot rock. Usually easy enough to eyeball but both have to agree by tapping the shot rock with their broom or kicking it towards the centre if they know the other team is shot. Can also be measured by an official at the request of either third.

Freezing: Putting one rock as close as possible on top of another. This prevents the other team from being able to take both rocks out at once if they're close enough, the top one will be frozen in place. Often done on the opposing team's rock if it goes past the tee line. There's a lot of strategy involved based on who has the hammer but it's usually obvious which team needs to keep rocks in the house by how they play.

Free guard zone: completely forgot about this one I haven't played in a long time. For the first four rocks the guards (in front of the house not counting for any points) are not allowed to be taken out. Teams can slightly get around this by having the lead "pick" off a centre guard, splitting their rock and the guard to either side of the house (without taking it out of play, if it hits the side it gets reset). Having the centre clear is better for the team with the hammer, and they'll like having outside guards so they can have rocks in the 8-12 ft rings with the chance of scoring more than one with the last rock. (better explanation)

Hammer: the team who gets to throw last rock. On TV it's shown by a little yellow arrow beside the team who has it. If you score in an end you lose the hammer, which is why teams throw away rocks for a blank to try to get more than one the next end.

Stealing: Scoring when your team doesn't have the hammer. Essentially you have to prevent the other team from being able to get shot with the last rock and it usually starts with setup from the lead's shots.

Touching the rocks (burning): If the throwing rock is touched (likely by the sweepers' brooms) between hog lines it's burned and stopped. If it's after the hog line they call it out and let it continue, and the opposing skip decides if he/she wants to let it play or reset. Not exactly common.

Moving any of the other rocks in play: This is more common especially when the sweepers aren't watching their feet with a lot of rocks in play. Also happens with heavy peels/takeouts with rocks bouncing off the side. Rocks get reset and officials might have to step in to help with placement but it usually just takes the other team to agree.

Breaking a rock (seriously): If you break one of the 40lb granite stones into little pieces, the biggest piece counts and you put a new rock it's place. A little bit rare.

Complicated, but fun!

More:

http://www.reddit.com/r/Curling/comments/1wnyoe/rcurlings_introduction_and_faq_to_olympic_curling/