The Maturation of Video Games
1up.com is running a piece examining how video games have matured since the early days. The article explores what the social context of gaming has been, from Hunt the Wumpus to 'Hot Coffee'. From the article: "The maturation of games might be viewed more accurately as a climb into a unified grace. By the time console gamers were wowed by Sonic The Hedgehog's 64-colour world, computer gamers were already familiar with zooming across galaxies, building cities and landing virtual planes. The 486 ran at 66 mHz and had the capability to create 3D texture maps. 16-bit consoles, which ran at 7 mHz, could not replicate a game as impressive-looking, innovative and as huge as Doom."
Besides, someone else already pointed out it was ported to the 1.xMhz SNES cpu (with help of the mode-7 hardware).
Forget Mode-7, the SNES version of Doom had a SuperFX chip in it. For those who don't already know, the SuperFX is a dedicated 3D chip that was used in games like Starfox to generate 3D graphics. So even though you can get a SNES version of Doom, it's not really a stock SNES in the strictest sense.
Oh, and the SNES's CPU (a 68C618) actually runs at 3.58 MHz. When the original article refers to a 16-bit system running at 7 MHz, they're most likely referring to the Genesis rather than the SNES (The 68000 in the Genesis actually runs at 7.67 MHz, but I've split enough hairs in this post already).
-"One machine can do the work of fifty ordinary men. No machine can do the work of one extraordinary man." -EH