I was sure that this was answered in a post somewhere in the forums here, but oh well here it goes again.

Hori had stopped working on DelphiX for whatever reasons [size=9px](I'll have to assume like most projects, lack of interest.)[/size] and moved onto a commercial project involving a library called TMpegEnc. It is assumed by most that followed DelphiX when it was still being developed that he had finally gotten a full time job in the industry and kept busy enough that he just didn't have time for it anymore. Add to the fact that his English isn't [size=9px](or at least wasn't then)[/size] that great, so whatever non-Japanese speaking/reading audience he had sort of fell off the radar.

That is the story of Mr. Hori as I know it.