How worried should we be about solar storms?

The Sun is entering a period of seriously intense solar activity, releasing huge volleys of charged particles and plasma blobs into space, including the recent Valentine's Day X-class flare, the most extreme in years. So how much of a threat do these flares really pose, and how prepared are we for a seriously… » 2/20/11 3:30pm 2/20/11 3:30pm