The Nvidia Shield Tablet 4G LTE 32GB can be pre-ordered already, while the release date so far set to September 1: http://www.amazon.com/NVIDIA-Shield-940817612500100-8-Inch-Tablet
The price for the Nvidia Shield Tablet 4G LTE is $399, so just $100 more than the Wi-Fi edition of the tablet.
The 16GB Wi-Fi Nvidia Shield Tablet was released just two weeks ago, so we didn’t have to wait long for the LTE version fortunately.
Nvidia Shield Tablet 4G LTE model use the same Nvidia Icera i500 modem that even Surface 2 went with, and so far in the US the 4G LTE model will support both AT&T and T-Mobile. In addition to the LTE connectivity, the tablet also has twice the memory of the Wi-Fi model, at 32GB, and even supports microSD cards up to 128GB.
Other than that it has the same 8-inch 1920 x 1200 screen, 2.2GHz Tegra K1 processor, integrated stylus, dual 5MP cameras, and the otherwise same attractive package as the 16GB Wi-Fi Nvidia Shield Tablet.
– Jim Miller