...And "The Legend of Zelda" (Nes) has not been put on this thread why? WHHHHY???

For it's time and the things it did it was revolutionary.
I typed that list off the top of my head; it's far from a final draft. I agree that the original Legend of Zelda deserves a spot in a required curriculum.
Does Mega Man 9 really represent anything different than Mega Man 2 though?
Yes. Very much so.
Nine is also too new to be called history but that's just my opinion.
MM9's importance in the industry has yet to be fully realized. Capcom and Inti Creates purposely restricted themselves to using basic building blocks--no first-person perspective, no high dynamic range lighting, no complex mechanics--to create a game that exemplifies the "purity of purpose" and tight level design that made Mega Man a classic series, thus proving that some elements of gaming are timeless.
The developers also incorporated newer features like downloadable content, achievements, and online leaderboards without compromising the gameplay experience.
More importantly (in the eyes of other developers), Capcom and Inti Creates turned a profit. In a few years, it's very likely MM9 will be designated the flagship of the Retro Renaissance.
Excepting Radiant Silvergun (Saturn)
RS is widely regarded as the greatest shmup ever made.
KD is one of the best modern examples of "beauty in simplicity" game design. The concept is simple: roll things into a ball. The controls are simple: the player uses only the two analog sticks. KD deftly blends new technology and old school simplicity to create a remarkable title.
and Soul Bubbles (DS) (which I don't know enough about to comment on)
Soul Bubbles is most relevant as a representative of indie game development moving further into the mainstream as well as an example of emerging game design philosophies.
I suppose as this is a history lesson and not a "best video games ever" list that my students should play a Sonic the Hedgehog game as well. Although Sonic never held my interest the overall rivalry between Nintendo and Sega shaped video games a lot and should be represented. There should probably be a representatives of all the major genres as well.
Agreed.
On a side note, I loved the Sonic series on the Genesis (especially Sonic 2).
For the 2-D fighter genre I am thinking Street Fighter 2 as the one that shaped it.
I was thinking over the list last night while brushing my teeth and Street Fighter II came to mind.
My wife asked me what game I would choose to represent the brawler genre, and I said, "Streets of Rage 2, of course."
A FPS selection is kind of difficult. Wolfenstein started it all but that doesn't show the online multiplayer aspect so I guess you would need something for that too. I am thinking Quake but I've never played it.
If I had to pick one first-person shooter as the most important, it would be Doom, without a doubt. Doom was a big step in terms of technology, made LAN gaming widely popular, and was one of the first games where players could create their own levels and heavily modify the game.
Although dead as nails today the point and click adventure game was popular at one point. I am thinking Monkey Island 1 which shows how the interface evolved from its text based ancestors.
I discovered the adventure genre with Kings Quest VI, but I'm sure there are older titles that are more significant than KQ6 from a historical perspective.
As popular as they were in Arcades there needs to be a light gun game but I don't know them very well.
Agreed.
I'm not sure exactly what to drop into this slot, though. Any suggestions?
Something representing the FMV craze should probably be shown, maybe Final Fantasy 7 IDK.
FF7 should be on the list for a number of reasons, even though I still strongly dislike many of the game's characters (including Cloud). Still, I can't deny the impact FF7 had on the RPG genre both in Japan and in America.
EDIT: Dragon's Lair. That would be the best representative of the FMV craze.
The fan base of World of Warcraft probably dictates it's coverage but that's not a comment on it's quality.
Maybe we could just show the class the Leroy Jenkins video and call it even.
/grin
In all seriousness, WoW is a very important title for a number of reasons, regardless of whether I think it's a grindfest or not. (What college professor do you know that doesn't inject their own opinion into their lectures?)