The new installer will include some updates to the actual scenery for v4 (and v3, hopefully), as Nelson was always a FSX scenery tweaked for Prepar3d. Incorporating a few modern Prepar3d features certainly improves the look of Nelson, especially in v4 -- I've seen some comments on the forums stating that v4 is the first real leap forward that we've seen for a long time, and I see that myself. Even an old scenery like Nelson starts to look closer to reality with just a few feature tweaks. I can see why some developers are looking at x64-only projects.
Here's a peak in v4. As I said, the scenery tweaks are finished, the installer is not.





