I think we can all agree that Nintendo's marketing lately is a clear step forward in comparison to their efforts in 2012-2013 (which were, to put it simply, complete garbage). While their current strategies still pale in comparison to the brilliant 'Wii Would Like to Play' and 'You're Playing with Power' campaigns, I feel as though they're still necessary steps in the right direction.
Since the launch of Donkey Kong Country: Tropical Freeze in February 2014, every single major Wii U title has received a TV commercial (this includes, but is not limited to: Mario Kart 8, Hyrule Warriors, Bayonetta 2, Super Smash Bros. Wii U, Captain Toad, Kirby & The Rainbow Curse, Mario Party 10, etc.), some getting more of a marketing push in addition to that. For example, Mario Kart 8 had a pretty substantial campaign which included getting a free downloadable game when registering it on Club Nintendo, free Mercedes-Benz DLC & commercial (in Japan), McDonalds Happy Meal toys, etc. while Bayonetta 2 was featured in a Playboy photo shoot featuring playmate Pamela Horton, in which she cosplayed as Bayonetta herself. Furthermore, many of these titles received their own Nintendo Directs prior to launch and a few of them were bundled with the Wii U.
As for the 3DS, its marketing efforts were always a vast leap ahead of the Wii U's, but similarly to the Wii U, its television presence was lacking up until February 2014 (when Bravely Default released). Since then, commercials for games such as Kirby: Triple Deluxe, Yoshi's New Island, Mario Golf: World Tour, Super Smash Bros. for 3DS, Fantasy Life, Pokemon ORAS, Monster Hunter 4 Ultimate, Majora's Mask 3D, Fossil Fighters: Frontiers (and more) have launched.
In fact, just last month, with the release of the New 3DS, Nintendo began their advertising of the system (as well as Majora's Mask 3D and Monster Hunter 4 Ultimate) during TV shows The Walking Dead and Better Call Saul on AMC. In Japan, they've consistently been pushing games such as Xenoblade Chronicles X and Splatoon through convention demos, monthly streams, store displays and weekly coverage in Famitsu. Just this past week, Nintendo invited many media outlets (including Playboy and multiple Youtube channels) to get a preview of Splatoon and allowed them to capture their footage and share it via their respective websites.
Although these changes certainly won't cause the Wii U to rise from the ashes and become a commercial success, I do believe it's important that Nintendo is altering their ways and fixing their branding issue (slowly, but surely) to ensure that this disaster won't happen come the launch of their next platform. Things like this just don't fix themselves over night, and Nintendo knows that. Thankfully, they now realize that they can't just sell on word of mouth alone, and that marketing their products can make or break them.