Well, I have to say, this game is superb. Maybe I'm biased as I grew up in the era of the NES but the old 2D Mario platforming games are amongst my favourite games ever! Sure, I like to play modern games such as Modern Warfare 2 and while these are perfectly good games (which I enjoy!), I miss a time when games were simpler and you didn't need 80 fingers to play them...
Old skool Mario gamers will love it's nods towards Mario nostalgia - remixed versions of old tunes, old enemies, characters, level layouts, point scoring at the end of levels on flagpoles, card games in Mushroom huts - it has so many references to all the old Mario games that if you were a fan of them, you're going to be instantly won over here!
Currently, I'm only playing this as a one player affair... but the addition of multiplayer will make for some fantastically frantic and fun games! Having played LittleBigPlanet as a multiplayer, all I can say is that this game will blatantly work just as well - in fact, probably a lot better! I found LBP a very good game as well, but for me personally, it lacked the character of Mario.
This game is blatantly aimed at old skool gamers - this game starts off fairly easy but expect the challenge to increase throughout the game! It never gets frustrating and due it's simple design never feels unfair. No glitches, unfair deaths or alike here... it's all your own doing!
While this game looks superb, it doesn't push the hardware to the max. While some people may frown upon this, I think it is refreshing that this game revolves around gameplay rather than graphics. A lot of modern games are certainly guilty of this. Having said that, this game does look very nicely presented - and Nintendo have pushed the graphics as far as a game of this stature will allow.
Finishing note - I haven't felt this inclined to play through a game for a long time. Quite often I can only play a game for a short while before I want a break - this game makes me want to come back for more and I'm having to prevent myself from playing it in order to be more constructive with my time! All I have to say is that if you're an old skool game fan, a Mario fan or just want something more traditional and less complex (but certainly no less deeper) look no further than this game!