Surprised not to have seen a discussion already kicked off on this though understandable if some who post(ed) on here are on the inside and bound by NDA.
This is a very welcome step forward for our hobby and as I've noted on other forums unlike N3V with their "target graphics" Photo-Shop imagery of Trainz New Era (never realised) DTG have waited until they have an actual Alpha of the product to make the announcement.
Specifically from the POV of our focus on this forum, I hope we find out sooner rather than later what the implications for independent content creation are, particularly at the hobby level of time and money investment. It would be almost inconceivable (although not unknown - Run 8, WOS) to have a premium train sim product without a route creation sandbox. However that will be of little use unless support is there for Blender, 3D Canvas/Crafter etc. as I certainly haven't got laying around nor would I wish to spend £1000's on 3D modelling and paint software just to put together a few station signs or bridges.
Anyhow exciting times ahead and hopefully we will learn more over the coming weeks and months.