First beta releases are coming in a few weeks, probably in December.
The new version is based on .NET Core 2.1, so the minimum supported OS is Windows 7 SP1. The desktop GUI is Windows-only, but the command line version should run on recent Linux distributions and on MacOS 10.12+. It’s also possible to create a web GUI for all these platforms. Windows XP may be supported later if the code compiles for .NET 4.0 without major issues.