Is the OUYA a threat to the Wii U?:

Most obvious threat is the price: $299.99 for the Wii U Basic and $99.99 for the OUYA plus tax, 1/3 the price. (OUYA WINS Retail Price)

Both systems can output full 1920x1080p/60Hz/32-BIT via HDMI (Tie).

Excluding the super expensive WiiU pad, the other reason why the Wii U costs so much is because Nintendo had IBM make them a custom made processor. The 32-BIT 1.24 GHz Tri-Core (3) IBM "Expresso." Vs. the OUYA's 5-Core 2GHz Tegra 3. One core on each system is dedicated to the OS/background operations, leaving developers with 2 cores on the Wii U and 4 Cores at 760 MHz faster on the OUYA to utilize. (OUYA WINS in Processor Category)

Thanks to pause operation for the OUYA, both systems have 1024 Megabytes or 1 Gigabyte of DDR3 1600 RAM for developers to access. The Wii U features 2 Gigabytes only to have the Operating System hog an entire Gig of it (Half)! Furthermore, the Gigabyte that the Wii U has is then slip in half. 512 Megabytes to System and 512 Megabytes to Graphics. With the OUYA developers can decide for themselves how much memory to allocate to each section. This can come in handy for a game like Rayman Legends where you need a lot of system memory to carry all the 2D, high res sprite animations. Not a lot of video memory is needed there. On the other hand, say a developer is making a highly graphic intensive fighting game where there is only two characters plus an environment. More video memory is needed then system memory. The Wii U loses in the memory category since it limits the developers. (OUYA WINS in Memory Functionality)

Comparing to the Wii U Basic, both systems have 8 Gigabytes of internal flash memory storage that can be expended by external USB hard drives. However, the Wii U can only access up to 2 Terabytes and requires an additional power supply since Nintendo wasn't able to find a 5 volt reference line in their system to jump to the USB hub. The OUYA can access up to a 3 Terabyte hard drive and DOES NOT require an additional power supply. (OUYA WINS STORAGE)

Why the OUYA isn't Cellphone or Tablet Without a Screen!:

As stated above the OUYA's main CPU will be the Nvidia Tegra 3, but what is the difference between this Tegra and the ones found in cellphones and tablets?

Most mobile devices start off having the CPU clocked between 1.0 GHz-1.3 GHz, and sometimes 1.5 GHz to 1.7 GHz if you're willing to spend $300+ on the device. Out of box, the OUYA processor will be clocked at 2.0 GHz.

The Tegra sports 5 cores, 4-Main cores and 1 power-saving core. To conserve battery life, mobile devices use what is called pause operations and only uses either or. For example, if you're playing a game, typically the device is using 4 cores, 1 of those cores being dedicated to background operations, leaving developers with only 3 Cores to utilize.  However, if you're surfing the web/watching a movie/listening to music/and utilizing other small apps the 1-533 MHz power-saving core is used instead and the other 4 cores are turned off. In the case of the OUYA, battery life is not an issue since it is plugged into the wall. All 5 Cores will be utilized at the same time. 4 Cores mainly for developers, and the +1 667 MHz Core to process the OS/Background operations.

Now for the Nvidia ULP GeForce integrated graphics chip. In Cellphones and tablets the ULP is given 12-Cores operating between 416-520 MHz. While the cores may remain the same, although there are rumors that it could be bumped to 16 cores, the clock speed will be increased on the OUYA's ULP to 900 MHz.

Time to talk about Operating Systems. Yes, it's true that the OUYA is android based. 4.2 Jelly Bean to be exact. However it has been heavily modified and tailored to being a videogame system.

Other Notes:

Thanks to the Processor and the RAM, the OUYA is still capable of high-res textures, advanced lighting/special effects, full shadows, full screen anti-alias and physics to include Nvidia's own PhysX engine. The only thing it will suffer in is polygon count which will be between 180-250 million polygons per second. That is more than 4 times the amount of polys for the original Wii, Twice that of the 3DS and roughly 33% more than the Playstation Vita.
- Since the OUYA is android based, you can connect a blu-tooth mouse and keyboard to it and use it as a personal computer, especially using apps like Word/Excel/Power Point and other productivity apps.

The OUYA is not region locked and is completely open source. Even you could make a game for it. OUYA offers a free developers kit plug-in for the Unity engine. The Wii U is region locked and you have to be big like SEGA or Ubisoft to even think about developing for one of Nintendo's systems.

In 2013 Nintendo still does not believe in the indy market!

Worst case scenario, you buy the Wii U basic for $299.99 and the external hard drive for $79.99… You might as well pony up the extra 20 bucks and get yourself a PS4 if you want to see a significant increase in power!