Just thought I'd resurrect this thread as it helped me out a bit with the AVS special. Without having a sample, I've been debating what material to get for my 10 foot wide screen, G11, and soon to be Panamorph. Dean's screen is about 95 sq.ft. by my figuring and mine will be 54 sq.ft. With 1500 lumens, he is getting (1500/95*.85) 13.4 ft. lamberts. My size screen will get (1000/54*.85) 15.7 ft. lamberts. Of course this is all conjectured on JVC giving honest numbers on both projectors. In any case, even if the output is significantly less (750-800 lumens)the picture should still be darn good - in a darkened room of course.
There are varying "standards", and opinions, for how bright a picture should be, but going through these sorts of calculations may help give a better idea of what one wants.
Jay