Diggin deeper on James Krachts site I found some info on Unity.

James Krachts VLM Journal has a mini pressrelease which hints that the game is indeed kind of a playable geiss plugin:

MOLYNEUX AND MINTER TEAM UP

Lionhead Studios is delighted to announce a collaborative project between two of the games industry's most respected veterans, Peter Molyneux and Jeff Minter.

Lionhead Studios will work closely with Minter on a new game, "Unity" which is being developed for the Nintendo Gamecube, a new development platform for Lionhead Studios. Day to day development of Unity will take place in Minters welsh studio, but he will have access to all Lionhead resources including audio, game testing, production and PR.

Unity is a fabulous journey through a succession of beautiful abstract 3D spaces, with gameplay varying in tempo, from fast paced shooting to a more gentle progression. Audio effects will be closely linked with the games pace and tempo and will be an integral part of the playing experience.

The project is already five months underway and is to be the subject of an eight page Edge feature at the end of the month. The visual effects that Minter has already managed to create stunned even Edge's experienced editorial team.

In announcing this exciting collaborative venture Peter Molyneux said "Jeff Minter is one of the people that inspired me to get into the industry. I queued along with everyone else in the 80's to get his autograph and even considered getting a Llama! To be working with one of the founding figures of this industry is huge honour, I am sure we'll be producing a game that is amazing and unique".

Jeff Minter responded " "I am very happy indeed finally to be able to talk about this excellent collaboration between Llamasoft and Lionhead which will allow me to work on what is basically my dream project. The chance to undertake this work with the backing of one of the best and most respected development houses in the world, and with the guidance of some of the finest and most creative minds in the business, is perhaps the greatest opportunity I have had in my entire career, and I believe that together we can produce something truly extraordinary".

The site contains more information but you should check yourself. Just another quote: "In actual performance expect it to be a lot more dynamic - remember it is designed to be played by [up to] four people at once, and on this demo it's just me fiddling with each controller one at a time."

I found some more info on Unitys Background by visiting Llamasoft homepage, using the Mobygames Database and entering VM Labs and Nuon into google.

It was hard to get information about this game in the usual ways and its hard to describe it. But its now definetly the most interesting game for me this year and I can't wait to get my hands on it.

UPDATE! It IS a playable geiss plugin :) On the VLM-Journal the terms "Unity" and "VLM-3" are used for the screenshots. VLM was a feature in the Nuon-DVD-Processor which allowed DVD Players to display weird graphics according to the music. VLM-3 is a project by Jeff Minter in which he applied this technology to the Gamecube. Unity then evolved out of this.
I got this information from this Article here
Phew!

UPDATE 2! W00t :) Rex Crowle from Lionhead mailed me about the official Unity Website which contains only the pressrelease from above at the moment but will hopefully reveal more information in the future.