Even in bigger studios using Maya or XSI, scenes are split up in parts and later combined again in compositing programs like Shake. And usually there are huge renderfarms. At the studio that I work in (I'm a traditional animator myself, but there's a big 3d department), all computers are hooked up over a network, and render the scenes at night, when the machines aren't used for anything else. (And we're talking dual Xeons carrying gigs of RAM here..) That said, I think Poser is dead slow, especially when you compare the quality of the other render engines. And if I see what real time computer games are capable of doing, at multiple frames per second..