A new listing on Steam promises a May 1st release. There's no word on any PC-exclusive features, other than standard support for Steam achievements, leaderboards, and Steam Cloud. The listing does not mention a price, but the XBLA version currently goes for $10.
Given Fez's relatively unassuming nature, the game doesn't demand much. So long as you have Windows XP SP3, a Core 2 Duo 2.8GHz or better, 2GB of RAM, and "any OpenGL 3.0" GPU with DirectX 9, you'll be fine. You may want to invest in a strategy guide, however.
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