This might be a bit late for you, Mark, but you can find some more details under
Blu-ray in the UK, at
http://blu-raytalk.com/forums/viewfo...9a003467a2876d 
... and for 100GB and larger Blu-ray-compatible holographic discs you might want to look under
Blu-ray and Holographic Data Storage: 1TB and Beyond..., at
http://blu-raytalk.com/forums/viewfo...28f9c4ca448c17 :P