The company answered both of these questions in a new Shield-focused blog post this morning: the tablet-turned-console will begin shipping in June for $349 from a variety of online and brick-and-mortar stores, including Newegg, GameStop, Micro Center and Canada Computers. General pre-orders begin on next Monday, May 20th, but if you've signed up to receive Shield updates from Nvidia you can pre-order the device starting today. If you haven't already registered, those who do so between now and the 20th should still be eligible to buy the device before the unwashed masses have the opportunity.
At $349 the Shield is definitely more expensive than mid-range, pure Android tablets like the $199 Nexus 7, but compares favorably to the $329 iPad mini or the $399 Nexus 10 if the physical controller appeals to you. Given the form factor, however, the more apt comparison might be to other portable game consoles rather than all-touchscreen tablets. Here, the comparison is less flattering—Sony's PlayStation Vita starts at $249.99, while Nintendo's 3DS and 3DS XL start at $169.99 and $199.99, respectively. Android's versatility makes the Shield a bit more intriguing than either of those consoles in many ways, but you'll have to pay more to get that extra feature.
Most of the other facts about the Shield have already been public for some time, but we'll run down the full spec sheet again for your benefit: the Shield will be one of the first devices to include Nvidia's new Tegra 4 SoC, which is a substantial step up from the Tegra 3. It has a 5-inch 720p display, stereo speakers, and includes 2GB of RAM and 16GB of storage. Dual-band 802.11n and Bluetooth 3.0 provide wireless connectivity, while micro USB, microSD, mini HDMI, and a headphone jack round out the physical port selection.
The tablet also comes with what is essentially stock Android 4.2.2 with a couple of Nvidia-centric features tacked on, one being the Tegra Zone software and one being the in-beta software for streaming games from your desktop. Because they don't have to deal with carriers, Nvidia representatives told me circa GTC that the Shield should get its Android updates without much delay, which if true would be a nice change from the standard operating procedure.