Get set for more than two weeks of thrills on slopes, rinks and sled tracks as 2,500 athletes from around the world come to Vancouver, British Columbia, for the XXI Winter Olympic Games -- or 21st Winter Olympics. The show starts Friday as competitors walk behind their flags flag in a colorful stadium parade by more than 80 nations. America's 216 athletes will wear vintage-style jackets, turtlenecks and wool hats designed by Polo Ralph Lauren.
Opening festivities also will include the lighting of a traditional Olympic flame to end a cross-country torch relay and the premiere of a Haitian earthquake relief music video by more than 70 celebrities singing We Are the World.

Televised action runs through Feb. 28 with activities that include ski jumping, snowboarding, bobsledding, ice dancing, figure skating, hockey and downhill racing. Athletes also will try for gold, silver or bronze medals in sports that are not as well-known -- such as the biathlon (cross-country skiing and target shooting), curling (sliding heavy granite "stones" on ice), luge (one-person or two-person sleds that exceed 90 mph) and skeleton (face-first sledding).
Americans with a shot at glory include snowboarder Shaun White, skier Lindsey Vonn, speed skater Shani Davis, ice dancers Meryl Davis and Charlie White, and hockey captains Natalie Darwitz and Jamie Langenbrunner. They and others will keep fans posted via Tweets, which the International Olympic Committee last week said athletes can send "as long as it is about your own personal experience at the Games."

The Winter Olympics, held every four years, are a big deal for broadcasters and a huge challenge for Canadian security forces. NBC will show nearly 200 hours of coverage, with additional programming on the MSNBC and CNBC cable networks. NBC's website (www.nbcolympics.com) has a feed of Twitter message streams from more than 80 athletes.
Security precautions on land, air and water are led by the Royal Canadian Mounted Police and reportedly cost about $1 billion, five times more than originally estimated. The video below shows safeguards for athletes, fans and dignitaries.

U.S. skater says: "There are a lot of teams who have a shot at the gold medal and we're one of them, so it's a really exciting prospect." -- Meryl Davis, Michigan ice dancer

U.S. official says: "This might be the Twitter Olympics. It'll be interesting to see where it all goes. Our brain waves are now operating in a 140-character mode." -- Bob Condron, U.S. Olympic Committee spokesman

Final Olympic torch carrier: The person who'll light the Olympic flame Friday remains secret, but speculation focuses on Canadian hockey hero Wayne Gretzky or a representative of native people.