Yeah, I'd love to see this too.

It could be done as a standalone app relatively easily, as most of the building blocks already exist. Making it an image pan visual requires player code changes

There is already an image panner/scroller that IIRC can be launched from Hijack.

Album covers can be embedded into mp3s via IDv2 tags.
Current track can be obtained from /proc.

What would need to be done is to hack the image panner to look up the FID of the current track, and to extract the art so that it can be displayed.