The argument here was "well, if Apple can assume that users are going to learn a list of shortcuts, why can't Microsoft."
The answer is because the keyboard shortcuts on OS X are actually shortcuts, not required for using the operating system. The gestures Microsoft has incorporated in to Win8 are the only way of doing things, whereas I can do things a few different ways on OS X.
Let's stick with closing an app. Apparently the gesture is swiping from top to bottom on Win8. On OS X, I can do that by clicking the red button (arguably the most intuitive method), by going to the File menu, or the keyboard shortcut, Command-W.
How about Command-Tab? There's only one way to access that functionality. How do you capture a screen in OS X without the secret "shortcut" keys or the command-line? How about ejecting a secondary optical drive? Zooming in and out?
There are a bunch of ways to eject a drive: 1. little eject button in Finder, 2. Right click on drive on desktop -> Eject, 3. Drag drive from desktop to Recycle Bin (this one is weird, but intuitive for long-time Mac users I guess). I admit I may be misinterpreting what you mean by "secondary" optical drive.
System-wide zoom is mega-situational. I'm sure it's useful for those with visual impairment, but I've never seen anyone use it nor have I had use for it myself. This is like complaining that high-contrast mode in Windows does not have an easy-to-access menu.
If I had two disk drives, I'm not sure which it would eject. I suspect that this is what WayneDB was referring to.
Capture a screen? Grab.app
Eject secondary drive? Drag it to the trash can.
You got me on the zoom in/out. I don't know that one. But I could make an argument that this one is not a shortcut, but the only command, as it falls under accessibility.
Then let me enlighten you. Your ctrl-alt-delete example is poor due to the fact and this is backed up by a Bill Gates interview that that command was meant for debugging and was not supposed to ship in the final product. People started using it and they had to leave it in.
Some music players do not use space for pause/resume.
As for clicking and zooming, these things are so intuitive that children can learn on their own how to do these simple tasks. OLPC and other organizations air drop laptops into Africa and people who have never a seen a computer get them and teach themselves how to use it and how to read.