Wind Waker w/o a doubt. Pikmin 3 is really fun, it's a good game but it's a incomplete game. It's way to short and has a more than lackluster ending showing under the spotlight how incomplete and to short this game is.

Wind Waker on the other hand is a epic 15hours+ adventure in a open world vs a game that lasts for about 8hours tops that is made of small lvl after small lvls.

Btw you should of added a poll to this thread!

Oh I thought you meant the worst Zelda game in the Mario series. 

If you already have WW on the GC there's you definetly go with Pikmin. If not WW.

If you haven't played the original Wind Waker, you might want to consider that. If you haven't played Pikmin 1 & 2, that's another reason to consider Wind Waker and waiting on Pikmin, though by all means, Pikmin 3 can certainly be enjoyed without prior knowledge of the series, and honestly, with the changes to the controls, it might be easier to learn Pikmin 3 if you HAVEN'T played the other Pikmin games.

Like many have said, you can't go wrong either way. Both games are stellar and you absolutely must get both eventually.

While Pikmin 3 does retail for a higher price (making it the better one to get for free in that regard), I'd personally have to recommend Wind Waker if you've never played it before. The Gamepad enhances its gameplay better than any other game IMO and the download will take up less room on your WiiU to boot.

This is a really hard decision. While Pikmin 3 does retail for a highter price and it is very good, WW is a master piece.

Try to get both eventually, that's the best advice i can give.

They are very different games. That's all I can say.
Watch some videos of Pikmin games. That and commentary should help you decide if you'll enjoy Pikmin 3.
And I can't not recommend Wind Waker personally, so...

I'd go with Pikmin, cause I'd rather have a retail copy of Zelda.

If you haven't played Wind Waker, then get Wind Waker HD.

If you have played Wind Waker, and you loved it, then get Wind Waker HD. It's seriously amazing.

If you thought Wind Waker was meh, get Pikmin 3.

If you look on ebay you can get the download code of windwaker for half its retail price so I say go for Pikmin 3