The two games you mentioned were not well backed. Atari rushed those games out the door....with Activision they were given much love, money, and time to finish it right. From what I hear and what I've seen, it'll be worth the wait.
Well Arcanum was Sierra and Troika had plenty of time. Sierra even sat on the game for 6 months waiting for localization and Troika couldnt even be bothered to start work on patch until the game was actually released.
I wont disagree with you that TToEE was rushed out the door, but an equal share of the blame goes to Troika. They failed miserably to deliver a stable, or even complete by some measure, product on time. Who knows what happened from there in terms of Atari and Troika's dealings. Suffice to say the customer got screwed.