Interesting, in a way deserving for the way the US ignore International TEAM sport competitions (like The basketball World Championships and World Cup Soccer). This is a little taste of the US's own medicine. http://sportsillustrated.cnn.com/olympics/news/2002/08/28/dropping_sports_ap/
they've moved to drop baseball and softball in favor of golf and rugby don't worry though... i've heard they've added chess as well.
I don't know about golf but assuming they add Sevens rugby, I think it's a good move. Sevens can use the same fields as soccer, requires less players than baseball, each match is 20 minutes long (iirc) and one team can play 3 matches a day, it's perfect for a short event like the Olympics. It's also one less stadium (that will go unused) the host city has to build.
Yes, and I can tell that you want to know more. It's been a medal sport since Barcelona '92 and a demonstration sport in '84 and '88. It has been an exhibition sport a few times, as early as 1912. Cuba has two golds and a silver while Japan has a bronze and a silver. Can't think of anyone else who's done well...
Japan has won a gold. United States. Holland was the first team to beat Cuba in the Olympics. Strange, but true.