If they are broadcasting in UHD then its possible that there would be some benefit in clarity even on the downscaled 1080 HD broadcast.
I remember saying back during the Malaysian GP weekend that I thought the image looked sharper & colors more vibrant & I have noticed the same at Suzuka & this weekend so something seems to have changed either at FOM or Sky.
I put together this comparison earlier in the year between the old OnBoards & the new HD ones:
http://screenshotcomparison.com/comparison/165970
Its not the best as far as looking at trackside objects goes but you get a good idea of the difference in quality by looking at the increased details on the wheel, around some of the antenna's on the nose, sponsor logo's & the colors etc... As well as the lack of up-scaling artifacts around those objects that you see on the old SD cameras.
It seems that this BETA app also includes a different timing screen, At a guess i'd say it could be something akin to the
Data channel &
new timing screen that Damon Hill tweeted about a few races ago.