Robin just pointed out that THQ is laying off a ton of people as well as EA. Paradigm Entertainment has been closed, one third of the staff at Juice Games in the UK has been laid off, Mass Media has been closed, Helixe may have been closed, Locomotive Games has been closed, and staff from Rainbow Studios has been laid off.
One plausible theory I heard is that it makes good business sense to contract now and hoard cash, so as to be better prepared for when things get better again in a year or two. It is no surprise that EA and THQ, big public companies, do this first. (I am also hearing rumors of a hiring freeze at Ubisoft.)
This means that companies that don't lay off people may wish they had in a year or so, and may then become prime takeover targets - for EA and THQ. I wonder if Blizzard Activision might lay people off to be seen to do the right thing and to get rid of dead wood, even though they might not need to do so because of the money they are making with WoW.
In any case, as Alex pointed out on Twitter recently, working for a big, publisher-owned development studio is no longer a guarantee of safe employment (if it ever was).