At least, Matt Matthews at Gamasutra doesn't seem to think so. And he has lots of fancy charts and graphs using real live "numbers" to back up his view. His interpretation of the data is that Nintendo is basically still doing business as usual the same as the GBA / DS eras, without any hit, although his interpretation also requires considering the DS an anomaly of sorts.
I don't know how relevant Japan is in this discussion. They seem invincible over there, in big part thanks to Monster Hunter. But they also already announced the follow-up to their huge casual game, Tomodachi Collection. Oni Training is selling very well, and so is Girl's Mode/Style Savvy. And of course NSMB2.
NoA is way more conservative and can't really rely on the same franchises to push the 3DS to new heights. And they don't develop games, they just sell them.
People will always have phones, and may play games on their phones after buying them. Nintendo and Sony should not try to go after the casual market. It's an uphill battle. Instead they should focus on providing more worthwhile games like Paper Mario and the like. Games that the dedicated gamers want and will purchase. What both console needs are games.
@kriswright Really? Pushmo is awesome but I don't think it has the kind of mainstream, casual appeal of the "non-games" and such. Still, apparently we're not the only ones who have played it, Pushmo is one of the best selling eShop games and is getting a sequel so... hopefully Nintendo sees that as a success and has other internal developers do eShop games as well.
ALSO: TRAITOR CONFIRMED. Well. Don't worry too much, I'm some kind of a socialist (apparently?) who works for loan companies...