NVIDIA has generally been among the best manufacturers when it comes to timely Android updates. With semi-monthly software updates to the original SHIELD Portable and SHIELD Tablet, complete with bug fixes and feature improvements, there wasn't really any doubt that the company's new Tegra K1-powered flagship would be getting a Lollipop upgrade. Even so, NVIDIA went and made it official with the tweet below.
Android 5.0 Lollipop and more is coming to NVIDIA SHIELD tablet. pic.twitter.com/yOGKRuOoRk
— NVIDIA (@nvidia) October 16, 2014
Notably absent from the declaration was a date, but that's pretty par for the course for these things. For reference, the original SHIELD was updated with Android 4.3 four months after the software's release, and 4.4 came five months after. We can but hope that the SHIELD Tablet's more conventional form factor and (presumably) simpler AOSP-based software can be updated faster than that.
NVIDIA didn't mention an update for the original SHIELD, but considering that the gaming device is still at parity with most Android flagship phones in terms of hardware power, I'd be very surprised if it wasn't on the drawing board. Less certain is the Tegra Note series of whitebox tablets: while NVIDIA technically handles the software updates for its various hardware partners, some of the tablets have been considerably late with new Android releases.
Source: NVIDIA Twitter