So, in the same way arstechinica gave a estimative of steam sales some time ago, a website was created that gives estimative sales of steam for all its games.
Not exactly precise, since they give a margin about how much can be, but developers ahve given a tip saying that they are actually in point about that margin:
Interesting tibits:
Shovel Knight 190,405 ± 21,556
FINAL FANTASY VII 827,849 ± 44,885
Valkyria Chronicles 262,364 ± 25,299
Age of Empires II: HD Edition 2,181,063 ± 72,637
Street Figther IV 102,526 ± 15,821
Still in alpha.
"Hardware design isn’t about making the most powerful thing you can.
Today most hardware design is left to other companies, but when you make hardware without taking into account the needs of the eventual software developers, you end up with bloated hardware full of pointless excess. From the outset one must consider design from both a hardware and software perspective."
Gunpei Yoko