Of course they don't, but you only have so much money to work with.. and most of it seems to go toward the visual assets.
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Yep, this tyranny of visual improvement is a factor of the marketing suits, not the developers, and as such should be discouraged.
I'm all for great graphics, but I'll happily play Deus Ex again and again, whereas the sequel just doesn't have it, despite being graphically superior.
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Exactly, solid gameplay will always trump visuals.
That's what good games are remembered for, that and story.
Look at Planescape Torment... graphics were ok, but the story... FAN-tas-TIC