Yeah i mentioned that, price cuts make my argument irrelivent. At full price Nintendo games continue to sell, and some of you are right, they have always continued to keep selling for ages. Casual is not an excuse.

The bigger question is the other way round - why do so many non-Nintendo games wither out after a few months?

I think it comes down to two things, competition and online play.

Big-budget genre games are in competition with each other for gamer attention. They have to get that attention through advertising, and given the competition you have to front-load the advertising dollars and push the game hard at release.

You then get diminishing returns from advertising spend further down the line.

The Nintendo titles have less competition (for example, there really isn't any serious competition to Wii Fit, there wasn't anything to match Pokemon, Endless Ocean is uniquely relaxing), so they need advertising for awareness, but the budget isn't pushed up by competition and they sell largely on word-of-mouth.

Online affects it because anyone who wants to play competitively online has to get in early or they will get continuously pummelled. Again this works to frontload sales.

Ok, three things, there is Nintendo's spectacularly good brand reputation. They don't do turkeys.

One element of a lot of Nintendo's games is how unique they're in the marketplace ...

When you see a good First Person Shooter released (pretty much) every month, a good platformer or adventure game released every 4 to 6 months, and a good Kart Racing game released every 2 to 3 years, this means that a Great First Person shooter has residual interest for a couple of months, a great platformer or adventure game has residual interest for a year or two, and a great Kart Racing game has residual interest for an entire generation.

Essentially, Nintendo's games tend to sell well over a long period of time because they produce the kinds of games that few other developers do at a quality level far above most of their direct competition which means that when people look for games in these genres the Nintendo game is the one that they buy. More developers would have a sales pattern like this if they focused on something original rather than producing a squad-based shooter with a cover system involving space marines fighting huminoid monsters.

Because money is the only thing that matters to them. But Nintendo thinks entertainment and money. Other japanese companys? SquareEnix, Capcom, Konami to mention the biggest. Sony dont make enough games by themself.

Advertising an older game is more cost effective for Nintendo than it is for a 3rd party publisher.  Nintendo is the console maker, publisher and developer of their game so they get to keep the approx. $30 a publisher would take in.  Plus the commercial also advertises the Wii or DS.  A 3rd party publisher will still take in the same $30 but they will need to pay Nintendo a licensing fee and a royalty fee to the developers.  So their return on each additional copy of software sold due to advertising will be a lot less than Nintendo's cut.

I think one thing that's dragging other companies down is their viewpoint; most of them only seem to understand three market segments: hardcore, kids, and casuals.  Many of Nintendo's games seem to try and break out of these limited boudaries, and treat the audience as a giant gradient as opposed to focusing on one group or another.  Look at Zack and Wiki, someone glancing at that might come to the conclusion that it's a "kiddy" game, and no one over the age of 8 is going to want to play that; but Mario has broad appeal that anyone could enjoy.

Evergreen= Sales consistently good over a long period of time.

AAA= Sales Amazingly good for a short period of time then drastically drops down.

 Thats pretty much what I was saying :/.

 Third parties work-around seems to be getting games with well known brand names, they don't need advertising as any Joe Public knows what Star Wars or Resident Evil is, and I'd guess alot of the Wii audience just buy games as 'shelf' purchases. They don't follow the internet hype, look at the metacritic score and debate the best possible release that month, they go in the shop and see what takes their eye. The only added expense for a publisher then is buying the best store spaces - and maybe license fees.

  This year I think the biggest third party Wii hits are going to be licensed software, or stuff with some sort of brand name. It gets around the whole advertising issue, makes your software stand out etc.

 The other thing we'll see is big money spent on trying to establish these brands - we're guranteed to see another de Blob, Boom Blox, Shaun White's etc because the money spent marketing them will be expected to not be needed for the sequel. I look forward to seeing what EA do with their Fitness game.

Nintendo understands what the market wants and reacts to it. That is the one and only way to make a successful product. Know your market, cater to it.

I'd say it's because Nintendo titles are so unique.

There is really nothing out there like Nintendo games, and with 30 years of high quality titles behind them, people know when they buy something that says Nintendo on it, it will be quality.