Not much surprisingly, despite it being around for many years. It will usually be labeled; HiP10, 10 bit, HiP. You will find that Blu Ray encodes are more 10 bit to save space, a really good encoder can get 1:1 visually at 1/5th of the size. It's amazing how much Data is used for RAW video.
Sadly I am unable to find a RAW screen cap straight from Television but, let's just say that if you are watching anime right now on a TV in Japan chances are it is 1080i and is upscaled from 480p, despite it being produced at higher resolutions. (I may be speaking under correction here, but when I used to use IRC I was on many of the fansub channels Taka, Dattebayo, SS, Leopard and they could confirm that it was mostly upscales to 1080i). I recall at one stage when Dattebayo was still around. They had stated that people should stop complaining, that Bleach looks "blurry" or "unclear" as they had posted a screencap of the TV Tokyo 7 RAW, and my word was it shocking, the interlacing was so bad you could see the banding.
...and here I am going on about TV broadcast video quality.
TL;DR
It will state 10bit, and not all of it is.





