It's almost warranted given the similar-thinking to Wii U (in the way a game can be streamed to the controller. Obviously Nintendo does it with their console, nvidia lost the console wars so their 'console' is a locking down a PC to their proprietary GPUs for a similar function.)
Also, they have gone out of their way to state games WILL be developed toward the thing, not simply limited to what will run on a standard Android device.
All-in-all, it looks very solid for what it is, the question primarily being if it has a place. Given there will be other mobile devices with strong GPU performance and similar abilities before too long, people seem content with the gaming ability vs convenience of their phones, and in your home you could simply use a (perhaps non nvidia-powered) PC...I don't know.
Looking outside the device it's important to realize what this REALLY is. This is nVIDIA's attempt to jump in front of the moving target that is mobile device performance and develop a standard. The more input they have in creating such a standard, the more control they have in how the market develops. That, more than selling any one device, is obviously their goal.
Given their approach to developing and emerging technologies/platforms, which is to lock them down and make everything proprietary so the consumer relies on their products as exclusively as possible rather than actually helping them reach the broadest base possible, I will be cheering for them to fail, just like PhysX, sli on only nvidia chipsets, CUDA, etc etc.
Again, it's not the tech, which is nice...
It's the methodology, which is quite simply evil.