I read somewhere (perhaps from one of the mods) that the Nuendo product is self-sustaining financially and I recall he said it is making money. Now whether or not that’s exaggeration or marketing is another issue, but as I understand it, each business/product unit in Steinberg has its own revenue stream and development process, even if they share components. And given that they’ve already made some changes to Nuendo (i.e. merging in the NEK features), and Nuendo’s recent success in the game dev market, it seems that it is unlikely that they are going to merge it with Cubase any time soon. If anything, I think it is really here to stay. They just launched Nuendo Live 2 as well, so the “Nuendo” brand is something they seem to be committing to.
Cubase and Nuendo obviously share a lot of the same codebase, and sometimes Cubase gets things from Nuendo, and sometimes Nuendo gets things from Cubase. I suspect we’ll get all the Cubase 10 features by Nuendo 8.5, plus some new goodies. Just a matter of time. And I’m not sure it’s a good idea to get all the new Cubase 10 features right away anyway, since there are often lots of bugs to be worked out. I hate to say it, but the quality control on Cubase does not seem as robust as that of Nuendo. Cubase 10 has new multi-thread/core improvements that probably need more time to be tested before moving over to mission-critical Nuendo environments anyway.
One of the big headline features is of course ARA support… which is still forthcoming in Cubase. I suspect that when the Cubase 10 update is released with ARA support, Nuendo 8.5 (guessing at version number) will be released in close proximity to it… so both will have ARA support at nearly the same time. It would be VERY frustrating to Nuendo users to have to wait very long for ARA support, now that it is known that Steinberg has been working on it. Perhaps they delayed ARA support for Cubsase 10 just for this reason alone… at least until Nuendo 8.5 is released.
My two bits…