Ever? Of course, with our days knownledge and his memory and calculating abilities, he is the best ever. For his days? Well i don't know, here didn't make up anything new, and i don't exactly know, when chess is mostly about memory now, he's abilities not really related to chess inventions.
Will Carlsen be Universially Recognized as the Best in History?

I'm not even obsessed with him, but to answer the opening question: IMO not a question of if, rather a question of when.
Then Fischer would be evaluated as "only" a player that participated in one title match, against one of the "minor" World Champions, and could not be ranked as one of the six-seven greatest players. Now many instead rank him as the greatest player ever, so it isn't just about title matches.
It's true though that many only count title matches, mainly because it makes things so simple. You get a nice and linear list, and won't have to think too much about if for example Anand and Gelfand really were the best players in the world in 2012, or if Euwe really was better than Capablanca in 1935.
Fischer's case was addressed above (by me, that is), and is night and day different, because of the socio-political setting in which his brief but meteoric reign happened. In other words, he attained "universal acclaim" for reasons that can't be repeated.
His is the only such case. There is nothing about Carlsen that is the least bit compelling to the mainstream media, so his legacy is going to have to be built on the first paragraph of his future wikipedia resume, which is as far as the universe is going to know about him, for the most part. And that paragraph will be a summary of his world title reign (or lack thereof).
I think he'll have a lengthy and spectacular reign...but he'll have to. He's certainly not going to be the hero of the entire western world, having toppled the unstoppable Soviet chess machine almost single handedly. Which, whether you feel Fischer actually DID or not, is certainly the story that his legacy carries. Carlsen will have nothing of the sort, so his legacy will be more easily and readily compared to Kasparov's two-decade reign of awesomeness. And he's got some catching up to do.
^^This!!

Yes it seems that many have made their mark on western society in that small yet unique window of time that was the late 1960s and early 1970s.
Not only that, but men of that era have still a strangehold on the establishment and media and aren't going to give up that power.
And why should we?
"There is nothing about Carlsen that is the least bit compelling to the mainstream media, so his legacy is going to have to be built on the first paragraph of his future wikipedia resume, which is as far as the universe is going to know about him, for the most part. And that paragraph will be a summary of his world title reign (or lack thereof)"
That Carlsen never will be universally recognized as the greatest ever is obvious, it doesn't matter which results he scores in the future either. No one is universally recognized as the greatest ever, and no one will ever be. At least that's what I think, and said in post #11.
Then it's another thing to discuss actual achievements, and how many players belong in the "top strata", why, and how to rank them. If winning title matches is what counts (except in Fischer's case), Capablanca could never be compared to Petrosian, Kramnik or Anand. Are Anand's four World Championship wins 2007-12 seen as making him much greater than Capablanca, who only won once?

Well, another thing to consider is a player's contributions to chess.
Carlsen plays well and probably has some subtle contributions to chess, but nothing famous yet. To my knowledge, there are no opening variations named after Carlsen (that is universally recognized as such) or opening lines that saw extensive modification by Carlsen. He is good at tactics and positional play, no doubt, but he is good all around and there is not one signature move that he has (unlike Tal's Queen sacrifices or Petrosian's exchange sacrifices). Likewise, his endgames are excellent overall, but to my knowledge, he does not especially excel in a particular type of endgame.
Contrast that to:
Kasparov - Kasparov Variation of Nimzo-Indian (4 Nf3), Numerous improvements to Sicilian Najdorf, Grunfeld, and KID
Karpov - Karpov Variation of Caro-Kann, Karpov Variation of Ruy Lopez, Karpov Variation of Sicilian Najdorf (6 Be2, though this is also sometimes called the Opocensky), Karpov Variation of Nimzo-Indian, Known for prophylaxis and strategic planning to such extent that there are several books written about them
Botvinnik - Botvinnik-Karls Gambit in Caro-Kann, Botvinnik Variation of Semi-Slav, Botvinnik Variation of English, Panov-Botvinnik Attack in Caro-Kann, Soviet School of Chess (mentored Karpov and Kasparov, among many others)
Fischer - Numerous improvements to Sicilian Najdorf and KID. Known for attacking chess - his "60 Memorable Games" remain a great textbook for learning that style of play. Great use of Bishops.
Carlsen - Only thing I can think of is some improvements to Ruy Lopez (popularized restrained pawn structure with d3 and e4, instead of the usual d4 and e4).
In sum, a Champion who leaves behind a considerable legacy of improvements to chess will be better recognized by new generation(s) of aspiring chess players as such new players learn from the Champion's contributions to chess.

Opening contributions dont turn masters into legends. Pal Benko is credited with the Benko gambit but his name is missing when we discuss the greatest of all time. Same with Sveshnikov, Ruy Lopez, Ken Smith, Ubik42, Reti, and Captain Evans.

I would also point out that in the age of computers, any number of good players can do the number-crunching to research a new line/variation...so it is less and less likely that a WC will become known for discovering anything major...moreso for popularizing something.
A lot more of the innovations, in fact, will probably start coming from centaur chess...

Opening contributions dont turn masters into legends. Pal Benko is credited with the Benko gambit but his name is missing when we discuss the greatest of all time. Same with Sveshnikov, Ruy Lopez, Ken Smith, Ubik42, Reti, and Captain Evans.
But, my point is greatness = Champion + Contributions (opening or otherwise) + other factors (politics, etc.)
Opening contributions dont turn masters into legends. Pal Benko is credited with the Benko gambit but his name is missing when we discuss the greatest of all time. Same with Sveshnikov, Ruy Lopez, Ken Smith, Ubik42, Reti, and Captain Evans.
But, my point is greatness = Champion + Contributions (opening or otherwise) + other factors (politics, etc.)
To me greatness in chess is only connected to actual chess results, at least if the discussion concerns who were the greatest players. If for example Carlsen scores better results in spite of having worse openings, I don't consider that as making him less great, it rather makes it clear how high his chess playing level after the openings is. If it is correct that he "does not especially excel in a particular type of endgame", I think that is less important than the fact that his endgames in general are very good.
Then Fischer would be evaluated as "only" a player that participated in one title match, against one of the "minor" World Champions, and could not be ranked as one of the six-seven greatest players. Now many instead rank him as the greatest player ever, so it isn't just about title matches.
It's true though that many only count title matches, mainly because it makes things so simple. You get a nice and linear list, and won't have to think too much about if for example Anand and Gelfand really were the best players in the world in 2012, or if Euwe really was better than Capablanca in 1935.