Foley effects are definately a key point for setting a particular mood, and since sound design is one of those areas that most people are completely clueless about, I hope that for their sake, Ambrosia includes a halfway decent library of effects with the CGE. Then again, we're going to be hearing the same effects from game to game...
If anyone is interested, I'll write a short tutorial on Sound Design on the Cheap with Macs... while I've got ProTools, samplers, Metasynth, and other fun expensive toys/tools, You'd be amazed by what a Radio-Shack Mic, Your run-of-the-mill Mac, some freeware / shareware, and a little ingenuity can do.
As far as music, all the great console RPGs have it, so why can't we? Ever watch a film with and without the background music? You'll have two completely different experiences.
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