Eventually, I recommend you get both (knowing that you're probably on a budget, I'd say get one console now and another in about six months). You will not regret doing that, you'll have best of both worlds. They're great consoles and I'm very happy to own them.
In my honest opinion, I've had more fun on the Wii U than I have with my PS4 so far. The games are bright, colorful, rememberable, and fun to play with others. There's so many great titles to choose from:
Super Smash Bros U, Mario Kart 8, Pikmin 3, Kirby and the Rainbow Curse, Donkey Kong: Tropical Freeze, Nintendoland, New Super Mario Bros. 2, Super Mario Bros. 3D World, Sonic Lost World, The Legend of Zelda: Wind Waker HD, Bayonetta 2, Captain Toad: Treasure Tracker, Hyrule Warriors, and not to mention Yoshi's Wooly World, Splatoon, Xenoblade Chronicles, Legend of Zelda U, Starfox U, etc.
However, having recently bought a PS4, it's also a fantastic system. The graphics are beautifully stunning and gameplay is like fluid.
Recommendations: Far Cry 4, Dragon Age: Inquisition, Infamous: Second Son, Last of Us Remastered, Grand Theft Auto V, Destiny, Battlefield 4, Watch Dogs, and Alien Isolation. There's great games coming out this year like Uncharted: A Thief's End, the Witcher III, Kingdom Hearts III, Batman: Arkham Knight, Metal Gear Solid V... just so many.
When it comes down to it... If you want hardcore, gritty, dark, sometimes depressing, but gorgeous games with intelligent storylines, go with the PS4. If you want colorful environments, pretty graphics, feel-good, relatively easy, but makes you happy, go with the Wii U. But please, in the future, do yourself a favor and definitely get both someday!

Good luck.