Pong and Super Mario Bros definitely deserve their spots.
Pong after all introduced people to both arcades, and also in a way home consoles (with the Magnavox Odyssey which was just a somewhat weird version of Pong with multiple rule sets, some weirder than others, although that's not exactly Pong but I like to group them together because of the similarity)
Super Mario Bros was not only very innovative and complex for its time, but was introduced with and bundled with the NES which many would claim saved the video game industry.
Doom I'm not sure about, one could argue that Wolfenstein 3D deserves the spot more since it was the very first FPS game, although Doom was more advanced it wasn't as revolutionizing, but it's the one everyone seems to remember the best.
As for Pac-Man and Tetris, I know they were massively popular but did they really revolutionize gaming? I don't think so, but if I lived at the time I guess I might think otherwise.
I don't think these games deserve the spots for being the greatest games in history, far from it -- but that doesn't seem to be the focus of the list either. It's more about games that had a big impact on the industry because they were new, innovative and unique, and those games certainly fit the bill.
Well, except for World of Warcraft. There were other MMORPGs that came out before it, introducing the genre and setting the bar for everything else. And I'm not familiar with most of them, but at least some of them had a huge game world with a lot of things to do, different professions you could improve to collect higher level materials and craft armor and weapons, cook food, etc. Basically all the things we have come to expect in today's MMORPGs have been around since before WoW, all WoW really did was improve upon what already existed. Not to say it wasn't great for its time, but some of the earlier MMORPGs deserve the spot more.