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There is an old Russian idiom that goes along the lines of: "The pessimists say it cannot get any worse, but the optimists say, yes it can!" Based on that phrase, I assume Russians in Chelyabinsk were unfazed when confronted with the meteorite that streaked across their morning sky on February 15. Sure there's fire in the sky  today, but at least it's not Valentine's Day again! (Forgive my burgeoning Yakov Smirnoff impression.)
I'm absolutely sure that you've heard about this meteor by now, but to help illustrate the event here are some related videos: Russians running from exploding glass; people in parking lot confused by lights and explosions; and dashcam footage of the meteor.
There are some sensible, lingering questions regarding this meteor event, which has a proposed name of the Chebarkul meteor. I've scoured the internet for some of the best, most-recent updates regarding this astronomical event.
What do we know about the Chebarkul meteor?
At the moment, very little; many news stories, government officials, and scientific reports have offered conflicting information.
 However, scientists have drawn conclusions that the meteor was likely rocky in composition, due to the fact that it broke up in the atmosphere and created at least three different explosions. Meteorites, or fragments of a meteor, have been found scattered in southeast-central Russia and northern Kazakhstan (home to Borat). Sonic booms produced by the explosions splintered windows and damaged 4,000 buildings in the Russian oblast, as well as injuring 1,200 people.
The explosion from the meteor was: brighter than the sun, according to NASA; occurred between 20--30 miles above the Earth; and released 500 kilotons of energy into the upper atmosphere, triggering a 2.7 seismic event on the ground. By comparison, the atomic bombs dropped on Japan in World War II release 16 kilotons. The asteroid entered Earth's atmosphere at an estimated 33,000 miles per hour.
 Estimates about the size of the meteor must make due, at least until Russian officials can better investigate a hole in a frozen lake reportedly made by a large fragment of the bolide. Most accounts believe the meteor was about 17 meters in diameter, but could have weighed between 10 11 tons and 100 10,000 tons. While speculative, most meteors are about 4.5 billion years old, so it's possible the Chebarkul meteor was much older than our planet.
Why didn't astronomers see this coming?
Many astronomers were preoccupied and had their underwear in knots over the upcoming appearance of 2012 DA14, which was an asteroid that was schedule to make incredibly close flyby of planet Earth later that day. Scientists have unanimously stated that there is no link between the meteor and asteroid, however.
 Also, most celestial object tracking systems do not have the capability of tracking smaller-sized objects. While terrestrially large, its relative stature was minor compared to many other meteors, asteroids and comets. The east-west direction of the meteor in the early morning (it was simply too sunny) and shallow angle of entry helped it evade telescopic surveys.
Why Russia?
Russia seems to attract incoming meteors and asteroids. Recall from Asteroid Self-Defense the asteroid impact called the Tunguska Event, which is considered the most significant Earth impact ever. In 2002, Siberia also was home to the Vitim Event. Since Russia covers 11.6% of the world's landmass, it makes sense that a significant portion of the bolides lands within its territory (though most bolides land in the sea).
However, Russia's high latitude also contributes to its large numbers of meteorites. Meteorites occur more often in the morning than in the evening since the hemisphere that is waking up is the also the hemisphere that is leading Earth through its orbit. Due to seasons, the leading face of the Earth is also a higher latitude, and with a large portion of its population living at high latitudes Russia experiences (and therefore captures) a large number of bolides that land within the country.
What can be done about incoming impacts?
While Russian Prime Minister Dmitir Medvedev argued for an international ballistic measure to safeguard the planet from meteors and asteroids, readers of Asteroid Self-Defense will know that is probably not the best way to ensure a collision-free existence. Rather exploding a bomb near the asteroid, or another method to revise the bolide's trajectory, would be most effective.
Coincidentally, on the same day Russia's southern skies were less than meteor-free, the United Nations was announced the creation of the Action Team on Near-Earth Objects. Run by the organization's Office for Outer Space Affairs, the team's mission is to determine an international warning system for incoming bolides, brainstorm deflection methods, and mitigate catastrophes when impact is inevitable.
 One of the team members, Dutch scientist Detlef Koschny, told SPACE.COM, "The day before we thought it is great timing that 2012 DA14 flies by in the evening … and were shocked when in the morning we learned about the Russia event. What a coincidence. Was this a cosmic warning shot? It makes you think."
Astrophysicist Neil deGrasse Tyson echoed that sentiment: "Asteroids are nature's way of asking: 'How's that space program coming along?'"
Resources
(Image credits: Houston Press; Fox News; NPR; Space.com; Philip Coppens; Washington Post)
Wikipedia - 2013 Russian meteor event;
CBS News - United Nations reviewing asteroid impact threat
Popular Mechanics - Three Questions about the Russian Meteor
Popular Science - Space Rocks 101: What You Need to Know about the Russian Meteor
Cornell - Ask an Astronomer: Meteors...
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