It was so successful he's hoping to do it again this year on 21st/22nd June. I've been talking to him and although he's planning to firm up details soon he's definitely planning on making it happen.
Would anyone be tentatively interested? Personally I think it's a great idea and being able to shoot in London with the added security of more photographers is a unique opportunity. Yes, 24hrs is a long time but it's once a year and we'd be doing this at our pace, wherever we wanted to go and with as many stops for coffee as we could possibly want! Sounds like a great idea to me

I've also pitched it to the camera club at work and two have signed up. If you're interested please let me know and I'll try to keep you abreast of developments.