Can't wait, it's becoming really usable (I always needed adjustment layers, and it now mostly has them). I wish they offered an appimage though, I'm not big on flatpaks due to size.
I was also wondering about this. Flatpaks apparently come with more libraries to interact with other Flatpaks, whereas AppImages tend be purely app-specific and their libraries are compressed for their usage only.
There’s third party Appimages. They also had a blog post discussing using Appimages for testing builds. If that gets done, I don’t see why they wouldn’t offer an official build.
In the release blog they mentioned working on appimage. Right now they are only using it for testing purposes and it should be compatbible with Debian. But there is no "official" distribution as of now.