There are no good answers to this question. It varies by title, publisher, platform, and region, and nobody likes to talk about their cut.
If you want ballpark numbers, I usually estimate 40% to the publisher (who must pay for development and marketing), 40% to retailer, and the remaining 20% is split amongst manufacturing, platform licensing, and distribution.
"The worst part about these reviews is they are [subjective]--and their scores often depend on how drunk you got the media at a Street Fighter event." — Mona Hamilton, Capcom Senior VP of Marketing
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