Well, after getting some more hands on time with the Shield I feel comfortable in giving a review.
The first thing that is on my mind is a little frustration. See, the pc streaming feature is still in beta. And even though I have a computer that passes all the requirements, they still can't find each other. After browsing through the forums it appears I am not alone. I think it might be because I am outside of the usa (Canadian), but with the other posts I feel comforted in knowing I am not alone, and that this beta feature will probably need some more patches before I can work it.
With that out of the way, lets talk about the non beta features.
The first thing that impressed me with the device is the weighting. There is enough mass that it doesn't feel cheap, and the controller itself helps counter the weight of the screen. This counter weighting helps tremendously for arm/hand fatigue.
The screen, although not 1080p suits its purpose well. The hand controller makes me naturally hold the device further away from your face then I would my super phone. It is bright enough to be used outside, although it isn't bright enough that you don't have to squint to see it in bright sunlight.
The speakers are truly impressive. They are on par with what I thought the htc one speakers would sound like. They are clear and loud and you can feel their bass vibrate through your finger tips. They don't have headphone fidelity/clarity, but you won't be straining to listen to them in a crowded room either.
The shape of the game pad reminds me heavily of the old xbox duke controllers in both size and shape. Depending on your personal preferences this could be a good or bad thing. To me, I like it, and the shape also helps balance the controller as mentioned earlier.
In use, the hardware really does shine, web pages load blindingly fast. In particular, kinja actually seems to be hassle free on the device, where as my htc by comparison quite regularly hangs up loading pages.
The device has full access to the android play market. The only potential hickup as far as apps go happens with apps designed to be run in portrait mode on a phone. To play these it is easiest to play at a table folding the screen all the way out and holding the device sideways. There is a menu of apps that were specifically optimised for the shield hardware. Playing these games/etc really allows the hardware to shine, give it a few months and you will truly have a ps vita/3ds competitor.
Speaking of competitors, the device supports emulators allowing you to play nintendo ds/etc games all without having to jail brake/root your device. That is a huge plus that helps make the upfront cost of the device more palitable. The most expensive game you will probably ever purchase is still a fraction of the price of its competitors.
Other neat features include the ability to stream your screen to a wifi compatible tv (this feature requires a tv with the same wifi feature). If you are stuck with a dumb/incompatible tv like me, it also comes with a built in hdmi out port.
Another neat feature is the ability to use the right thumb stick as a mouse. At first this feature feels difficult/gimicky, but after using it simultaneously with the left thumbstick which is better at selecting options/icons, its limitations are easily overcome and the whole procedure feels natural. This feel is huge, yes my xbox can surf youtube/internet on my tv, but with the shields four way input (touch/buttons/sticks/dpad) you don't feel hindered at all, especially when it comes to the touch screen keyboard. No, it isn't as good as a mouse/keyboard, but for use on a couch it is the best alternative I have tried yet.
Now the question you are probably pondering, or have already made your mind up about. Should you buy this device? At this moment, hold off, look at it again when you start christmas shopping. As with any system the kinks will be ironed out, and there will be an even more impressive optimized games list.
I will keep you updated when nvidia removes the beta status on the pc streaming. Apparently it can run Crysis 3 on max at 30fps*
*dependent on source computer and having a wireless n router.