Many people have heard of Oregon Trail. It's really just you.Meh, can't take such a list seriously from CNN. CNN never has anything to do with video games anyways.
Also, they are obviously just listing video game franchises because they don't know shit about the actual games in the series. The original Metroid over ANY of the future Metroid games? The original Metroid is the weakest game in the series. Oh wait, Metroid Prime is actually there, but it's on the 76th place, so that's waaaay behind the original Metroid, which Prime undoubtedly and unarguably pummels to death.
The Oregon Trail? A quick google showed it up as an educational game. Now I know quite a lot about video game history, but I've never heard of this one making any kind of impact, especially not compared to Donkey Kong and The Legend of Zelda. Either I just failed on Video Game history, or it's a piss poor attempt to make people play an educational game.
Anyways, not a good list. They don't know anything about the series they're talking about. There are a few exceptions like Diablo II and not just calling it Diablo, but then there's stuff like Mega Man. Could they be any more unspecific? Mega Man has so many fucking games, and the first one of them isn't even the revolutionizing one of them, that'd be Mega Man II. Seems like it's an article made just to gather readers.