Timothy Sphar, the director of International Astronomical Union, said in an email to National Geographic that asteroids like this pass close to earth all the time and this is a normal occurrence.
The Twitterverse was alight with comments:
jcsimonds: (Reno, Nevada) @slipdown "SpaceWeather.com issued alert (about asteroid near miss)." I can just hear it now: "Today there will b a near apocalypse"
yokamo: (Pacific) An asteroid the size of a 10-story building flew past Earth today about twice the distance as the highest Earth-orbiting satellites,,,wow
isko: (Hellsinki, Finland) WOW!!! this kinda puts things into perspective: "Surprise Asteroid Makes Near-Miss of Earth" http://bit.ly/ck1Dn 
garyobrien: (Charlotte, North Carolina) Crikey! Did we almost get hit by an asteroid? http://is.gd/ltgm
syael1339: I'm blaming the asteroid for the snow .... and for Rush Limbaugh.
NicoleLewis: Anyone know what time the asteroid will be passing us? Armageddon here we come 
