Mario has been the face of Nintendo for easily twenty years now, he's one of the most wide-known video game characters to exist to date. There may come a time where the old Italian will wear out, but it doesn't look like that'll be soon. Mario games still dominate the platformer games, and most people love a good platformer.
Mario? Hm... Relevant? Yes. Fun? Yes. Great? Definitely not. It's painfully obvious to see that there hasn't been anything new with Mario in years and anything that is new from Mario is largely forgettable. Mario games are extremely simple platforming games that anyone can pick up and play. That and the fact that the Mario brand is so well-known are the only reasons why people still buy these games. They're fun but I personally don't feel like they're fulfilling. I just see Mario as the equivalent of Call of Duty for Nintendo fans. There's a new game way too often and they don't bring anything new. The sad thing is though, Mario's been around so much longer so it's far worse in this case.
That article completely ignored Super Mario 3D Land. anyways, that's not entirely the point here. They need to bring innovation with each iteration. Super Mario 64 was the first 3D iteration in the series and it set the standard for all 3D platformers to come. Super Mario Sunshine introduced new, water-pack mechanics which was really interesting, although the game was still rather weak in some regards. Super Mario Galaxy introduced running around on balls and floating between one object to the next (oh! and GRAVITY, because apparently, that's in). Each game brought something new to the table. The 2D platformers in recent years, not so much. So I do think that Mario is still relevant and still innovative, but only in regards to the 3D platformers.Also, I was disappointed when they announced Super Mario Galaxy 2, because although I was excited to see the new additions and features and planets, it was the same thing as the first SMG, more or less and I had really wanted to see what they would bring to the table next. Mario isn't exactly known for it's strong story telling. It's simple, which is fine, but if they could make that stronger it would only help the series and bring back a Mario Renaissance, kind of like how Disney had their's. It's would be a return to form, only better.
I think Mario's okay. It's a nostalgia thing though. You start disliking it the newer it tries to be. I always thought NSMB was too easy and I hated it for that but then as time went by I actually started to miss it as it was a really easy way to play Mario on the go. Now Super Mario 64 DS is something entirely different. I had it, got all 150 stars, beat it and sold it and then a few months later I really regretted it. It was totally fun and the money I got from it was not worth losing it.