Huge asteroid to fly past Earth July 3

From USA Today:

An asteroid possibly as large as a half-mile or more in diameter is rapidly approaching the Earth. There is no need for concern, for no collision is in the offing, but the space rock will make an exceptionally close approach to our planet early on Monday, July 3, passing just beyond the moon's average distance from Earth.
Due to the proximity of its orbit to Earth [Map] and its estimated size, this object has been classified as a "Potentially Hazardous Asteroid" (PNA) by the Minor Planet Center in Cambridge, Massachusetts. There are currently 783 PNAs.
The latest calculations show that 2004 XP14 will pass closest to Earth at 04:25 UT on July 3 (12:25 a.m. ET or 9:25 p.m. PT on July 2). The asteroid's distance from Earth at that moment will be 268,624-miles (432,308 km), or just 1.1 times the moon's average distance from Earth.

I don't know about you, but that sounds pretty scary to me. How often does this stuff happen exactly? Maybe I should just go back to not paying attention. Maybe it won't even matter who the Democrats find to run in '08.