Just a curious question here. Would Mario, Zelda, Pokemon, and other games be so highly reguarded without their nostalgia factor? Nintendo has one decisive advantage compared to Sony and Microsoft; being that it's most popular games go back to the 90's and 80's. Sony comes close, but mainly only up the late 90's. Would games like New Super Mario Bros be so critically received if it was just a new IP platform game?

Personally, I think yes and no. Most games Nintendo puts out are quality on their own, even without comparing them to previous iterations. Zelda and Pokemon fit the bill here. But other franchises perhaps aren't that great compared to some of the other quality games. For example: I think Rayman Orgins/Legends is a superior platforming game than New Mario Bros (Wii/U). 

Want to know what you guys think. How much does the nostalgia factor play into Nintendo's success?

Obviously try to limit it to franchises that aren't new IP's. For example, don't talk about The Wonderful 101 because there is no game to compare it to. 

This game will never get bad, with or without nostalgia <3

Yes. I got into Nintendo in the Wii/DS era, so I can hardly say nostalgia has anything to do with my love for their games. If that was the reason I would still be with Playstation :D

Which nostalgia factor?

Their main games excel in creativity and design. There´s no need for such thing as nostalgia to appreciate that.

Well, nostalgia can be a double-edged sword. A critic could just as easily bash a new Mario or Zelda entry because it doesn't live up to the greatness of his/her youth as celebrate a new entry just because of its pedigree.

In my opinion, Nintendo games get consistently high marks from the media and consumers because they have been consistently great for 30 years.

I think nostalgia certainly helps, but Nintendo have it down when it comes to designing a game, especially platformers. Now, if they replace their next iteration of Mario with a different character and just re-skin it, would it sell as much? Probably not. That is where nostalgia helps, it lets them sell more. But the game itself would be solid with or without Mario.

Pikmin 3 is a really good game without any nostalgia in it.

I agree with what Veknoid says. Nostalgia can end up hurting a game's review score (just look at A Link Between World's review from Destructoid. The low review from them was simply because nostalgia, and an incorrect perception of previous Zelda games at that). Also an otherwise good game can be regarded as poor because it doesn't live up to the nostalgia.

as a person who started Zelda, 3D Mario,DK and SSB with the Wii they are good without the nostalgia

Yes. I started in 2012.