With Toontown, you could sort of see the writing on the wall. The game was cruising along in near-maintenance mode for at least a year, with updates being few and far between.
CoH was more of a shock because it was weeks (if not days) away from its next gigantic update, with promises of an entirely new story arc in the episodes after that.
That doesn't make it any less sad. I was reading the Toontown Central fan forums, and they're all heartbroken.
It really sounds familiar.
(Though, apparently, there is a ray of hope for them that there wasn't for us - one of the original Toontown devs, Jesse Schell has long since left Disney, and is now CEO of his own company, Schell Games. He's apparently expressed interest in buying and continuing the game with the Disney characters removed. It's not likely - he says there are lots of legal issues - but it's something to keep an interested eye on)