Lulz Security announced via Twitter that they'd taken down CIA.gov (which is, for the record, still incapacitated) a little before 6pm EST. No details about their methodology, or the motive behind/beyond the lulz. Which, really, who needs more reason than that to take on the intelligence wing of the US government?
At the rate Lulz is going, their conquests will be Napoleonic before the summer's out. And at this point, it's hard to see how they'll be stopped short of a land war in Russia.
Update: Looks like there may have been a motive after all, albeit an unlikely one. Apparently LulzSec was goaded into the CIA attack by random Twitterer Quadrapodacone, who repeatedly called LulzSec soft for attacking what he considered small-fry targets. And good news! He's still not impressed. So don't be surprised if CIA.gov turns into a hosting service for Mama Cass gifs before this whole thing runs its course. [LulzSec]