I think that it would be a harder decision if you were pitting the GCN againt the XBox OG. That said, with Wii U against XBox OG, I say that the Wii U wins this. Despite some of the comments here, I really think that Nintendo innovated heavily on the software side with the Wii U, especially once they started getting desperate. We got Splatoon, MK8, Super Mario Maker and BotW on the Wii U: we haven't seen a lineup like that from Nintendo since at least the early N64 era when we got the lineup between Mario 64 and Ocarina of Time in two years. The Wii U deserves recognition for this, moreso than the Switch which just got re-releases of these games.

That said, it's hard to really compare a Ninty console against an MS one. Halo was an amazing game and you could argue that it beats everything on the Wii U minus BotW, but my experiences playing it were all on the PC, the only time I ever played Halo on XBox was at friend's houses and I felt the game controller was a poor substitute for a mouse and keyboard. Microsoft deliberately cannibalizes their IP by releasing everything on PC because, at the end of the day, a gaming PC is almost as much of a Microsoft product as an XBox is. It just makes it hard to say that a particular XBox console was amazing: it all kind of blends together in my view. The Wii U is more distinctive in my view, even if most of its lineup eventually ended up on the Switch.

Now if it was XBox OG vs. Gamecube, I would say that XBox would win this battle. In fact, I think that it was Nintendo's weakness during the GCN era that gave Microsoft the critical entry point that it needed into the market. Basically, the Goldeneye + Perfect Dark crowd that was firmly in Nintendo's camp during the N64 era migrated to XBox in the next gen leaving Nintendo only with the "kiddie" audience.

Xbox had jade empire half-life 2

I love the Wii U and the Xbox left a bad impression on me when I tried it back in the day, sooo.

I'm giving the OG Xbox this one. Owning a Switch has made the Wii U redundant. Even if it hadn't, while it had some good games, I would say that the Xbox was ahead of its time in a lot of things. Online play being a big one, but HDD inclusion, x86 based to help for easy porting between PC and Xbox, 720p support, unified system memory, etc. It is basically what modern consoles would become. I also prefer it's third party library. However, of course Nintendo's first party is unmatched I just didn't think it got as much first party support as other Nintendo systems due to them struggling with HD development at the time.

Yeah, I'd say so far the Wii U still has better first party support than the Switch does. 

With the amount of nostalgia a lot of the Nintendo community has for the Gamecube I suspect if that were made a poll it would be one-sided as hell with the Cube curbstomping the Xbox haha.

One had two of the greatest games of all time, the other had Breath of the Wild and Mario Kart 8

-Nintendo is my overall favorite gaming company
-I bought a Wii U on day one (pre-ordered, actually)
-I've never owned the original Xbox
-The Xbox 360 may be my favorite console of all time

I voted Xbox.

The library, for its time, beats the Wii U and even though it released over ten years earlier, it had features that the Wii U never properly got. The Wii U had an awesome library of first party exclusives and a version of my all time favorite game but the Xbox is just more complete.

OG Xbox by leaps and bounds.

Xbox had a ton of amazing games. Halo Ce is still my favorite game currently. There were great experimental games on Xbox, such as: Bloodwake, steel battalion, & brute force. There were Sega games like Jet Set Radio Future, Otogi, & Shenmue II. Microsoft’s first party churned out effort after effort. You could tell their games, and system, had teams working overtime to make theirs the best they could be. Not all of their games were perfect, and some of them straight up sucked, but the ones that were good were once in a lifetime experiences. I’m glad i invested my time into it.

Wii U was one of the laziest periods in Nintendo history. I really enjoyed the system for the time, but other than touch features and semi-portability, WiiU didn’t create anything huge (Except Xenoblade). Everything was a port of something that was done before or could be played on a different console. I’ll say again, I loved the touch screen features. I also loved the web browser, Miiverse, tv remote. But the gameplay innovation/exclusivity was lazy.

I respect Nintendo for being fiscally responsible, and I consider Microsoft very wasteful, but as the consumer I got more of what I wanted from the OG Xbox.

Not just that but i liked the way the second screen functioned.  Was well done with some games and also was great for multiplayer.  Being able to play on tv and on the screen. Meant you could talk with the person sitting at your house and both play on your own screen.

Even the way it handled backing up of files onto a HDD and save files. Just seemed a more user friendly experience and even the apps it had.

I'm pretty sure that Nintendo's worst selling system (and biggest flop) was the Virtual Boy. It had something like 15 games for the entire system's lifetime.

The WiiU was compatible with Wii and GameCube games, so is actually a good choice if you want to build a Retro collection in future. The original Xbox was Microsoft's first entry into console gaming, so selling anything at all was an achievement.

Real failures in the console industry aren't really coming from the major manufacturers - there are plenty of crazy startups popping up every now and then to try to build the next $100 games console.