It is quite possible that Avisynth will be able to use the current version of Neat Video plug-in for VirtualDub. We will look into this and I will post a follow-up here a bit later.
The latest version of Neat Video for VirtualDub (v1.01) can be directly used from AviSynth scripts and there is a section in the user guide that explains how to use it.
I would like to add my vote for a native version for AviSynth:
- Reduce color conversions
- Get the same speed as VDub (Until 1.5, NV through AviSynth appeared to be slower).