Everyone is blowing this out of proportion, that looks exactly like the posters over the Wii section of every GameStop I've been to in the past couple of years. Then, they served to inform customers about the differences between Wii bundles and models. Nobody derided their "marketing strategy" back then, because it wasn't marketing, and neither is this. It's information. It's a poster, a pamphlet. The entire purpose of this is to inform Wii owners of the differences between their current system and Nintendo's new console.
Yes, it is an attempt to convince people to buy a Wii U, in a roundabout way. But it's not an invalid or embarrassing attempt just because it isn't a mass-market sales strategy. It's a localized strategy for a specific target audience that isn't represented whatsoever on this site -- hence, none of us are likely to be interested in these posters. We are already informed.