The Tegra K1 device to play with was a NVIDIA reference design sporting their high-performance K1 SoC and running Android.
The speed and graphics capabilities of the NVIDIA Tegra K1 were stunning with this ARM chip embedding a full "Kepler" graphics core. Unfortunately they had no Linux 4 Tegra devices with Ubuntu or any other non-Android/Windows systems at their booth.
NVIDIA was quiet about when Tegra K1 is planned to start shipping. While the Kepler graphics core is capable of OpenGL 4.3, the NVIDIA representative I spoke with said it will be up to Google to decide what OpenGL version the Tegra K1 will officially advertise by their binary driver. It's more likely to just see OpenGL ES 3.0/3.1 advertised, which already supplies most of the GL4 functionality.
When asking whether the Tegra K1 will offer up any CUDA functionality on Android, the NVIDIA representative would not officially answer that question but hinted it would happen with "well, the Tegra K1 is a -- FULL -- Kepler core." For non-Android Linux users, the Tegra K1 uses the mainline NVIDIA Linux driver in ARM form.
Overall the few minutes of checking out the NVIDIA Tegra K1 on the reference tablet was great and I can't wait to get my hands on some K1 hardware for running Linux benchmarks. The Tegra K1 is already running the Phoronix Test Suite internally at NVIDIA.
With how great the Tegra K1 is with Kepler, I already can't wait for a Tegra SoC with a Maxwell core given Maxwell's incredible power efficiency.