It's designed as a video filtering framework (sort of like Avisynth) but unlike Avisynth it:
- isn't from the 90's
- supports native frame-based multi-threading
- is extensible (supports arbitrary per-frame metadata; new colorspaces can be defined at runtime, etc)
- is cross-platform
- ships with Python 3 bindings; no support for a home-grown scripting language is planned
- has a C API rather than a C++ API, so it's actually portable
- has native support for things like clips with changing dimensions and other properties, as well as clips with infinite duration
As JEEB said it also has an Avisynth compatibility layer that emulates the Avisynth 2.5 plugin interface; loading Avisynth plugins does not require Avisynth itself. Not all plugins are supported yet.
Doing something like this has been discussed for ages in the usual complaining-about-Avisynth circles, but now Myrsloik finally went and did it.
This is change. This is the future. This is vapour we can breathe in.
GET HYPE