Im a big Mario fan but I think releasing 2 'New' 2D Mario games in 1 year is a bit much. Below is timeline of Marios adventures

If we go back in time a bit we've only had the pleasure of 1 Mario game per console from the snes (Yoshi's Island is a spin off imo) right up to the DS. World - SNES, 64 - N64, Sunshine-GC and NSMB-DS.

That brings us up to the Wii and it started as we expected... a new (and fantastic) 3D adventure in Galaxy. Off the back of the HUGE success of NSMB on DS Nintendo decided to treat us to an all new console 2D adventure in NSMBWii. They were right to do so, great co-op gameplay and its sales showed people wanted it. Then Nintendo gave us Galaxy 2, which we're led to believe only came about due to low development costs because they had so many ideas/content left over from the original that it basically made more sense to release than to put it on the scrap heap. Personally I am glad they did as it's easily my fav 3D Mario game. 

Phew, 3 Mario's on 1 console in the space of 3 years (the previous 3 games took 10 years spanning 3 consoles).

That was fun... lets give the fat little plumber a break eh? What now Nintendo? F-Zero? Pikmin? Starfox? Earthbound? Whats that??? The next gen is starting, oh well.

So with new hardware comes new Mario's, their new 3DS handheld gave us 3D Land and WiiU is getting NSMBU. This leads me to the game which I really don't think needs to exist (for at least another 2 years)...

New Super Mario Bros. 2! I really don't think the time is right for this game, for the following reasons:

1. It will damage sales of the already released Super Mario 3D Land.

2. NSMB2 and NSMBU will be detrimental to each others sales and critical reception

These are only my opinions but I don't think there's space for two 2D Mario's in the same year, one 3D and one 2D MAYBE but even then I think 1 per year is more than enough.

IMO NSMB2 should come out in 2013/14 and a new 3D WiiU adventure should come out 2014/15

What do you all think?

PS sorry if this is a bit all over the place, it's 1am and I wanted to get this off my chest before grabbing some Zzzzz

EDIT

I thought I'd revisit this thread since the reviews are starting to come in.

It's as I feared. The reviews aren't very positive and it's very clear this is going to be the lowest rated mainstream Mario title to date.

They've rushed a game to the market instead of putting their effort into the one that mattered... NSMBU.

Because of this games drop in quality and the fact that there has been too much Mario recently will mean that sales will drop long term. This is going to affect NSMBU and the WiiU itself more than this game which is not good for Nintendo.

Why spend £250 (or whatever it's gonna be) on a new console to play ANOTHER 2D Mario when you played a poor one 6 months earlier.

Like I said originally NSMB2 should NOT exist, there was no need for it, 3DS was selling fine and Super Mario 3D Land had legs. Instead NSMB2 will kill 3D Lands legs and the 3DS will be missing a heavy hitter that has been wasted in a time the 3DS didn't need one.

This is a stupid mistake by Nintendo in the long term!

based by what nintendo said about fans wanting more mario, pikamin etc.. I'd say no.

Based on what will happen sale wise because of it I say yes.

Conclusion Nintendo need to stop listening to every word of the fans and go with their gut and provide variety of their IP characters.

All the Nintendo fans will tell you no and there's no way Nintendo can overkill with Mario; however, there was a time a few years ago when it seemed like Mario was losing quite a bit of popularity back during the N64 and Gamecube days and it could probably happen again.

Honestly, I think it might be some time before we hear another mario title announced. Who knows, though? If they announce another sometime soon, then I really think they are overkilling.

Nope - because they actually split out into different markets enough that the overlap isn't too bad.

There are quite different markets for the 2D/3D games and for handheld/console. Once you break them into the four categories that come out of that (Handheld 2D,3D, Console 2D,3D) they basically don't release the games that close together.

I really get tired of people complaining about having too much of a good thing. Halo is milked, COD is milked, Mario is milked. I have news for everyone, if it's still good it's not milked. Nobody is holding a gun to anyone's head making them buy games. I can't get enough Halo and I'm glad it's becoming a yearly series. Why would I want less of what I love if it's still of the highest quality? The same goes for Mario games. There's something for everyone and you don't have to buy them all.

17 games in 27 years doesnt seem to much for me....

And about NSMB2, its the perfect time, the 3DS needs a nice boost this summer, specially in the west...and i dont think it will canibalize the sales of NSMBU or viceversa, because are on 2 different systems, one portable and the other home console...

Too many releases in too short a time does kill a franchise though. Or even a genre - it's basically what tore the entire rhythm game genre apart.

However neither Halo nor Mario are in this boat - out of the current big games I'd say only CoD arguably is.

paper mario? :S