DDO developers laid off were Melange, ChainsawGolem, and TheRockingDead. All three were content designers, and are friends of mine.
TheRockingDead had been working on DDO for a long time. He made Rainbow in the Dark.
With them gone, there's four content designers left working on DDO. (Steel, DocOct, and two whom may not have forum names to my knowledge)
I'm not counting PurpleFooz because he's the lead designer.
There were some cuts related to DDO that were not design positions, as well.
So Maj is right that it's not half the developers. Three is still a big hit out of a development team as small as DDO's, though. I hope everything works out, and that all of my friends who lost their jobs today are able to land on their feet and find awesome new opportunities.
To my knowledge, the layoffs were sudden. No-one had any idea they were coming until it started with layoffs of temp employees last week.
As someone who has survived through Turbine layoffs before, I can tell you that it's a pretty stressful procedure. They ask everyone to sit at their desk and wait for an e-mail telling you if you still have your job or not. I don't envy anyone at Turbine right now. It must have been a pretty awful day.