Here's the final lineup with my ratings. (*) indicate the number of votes for WOTN. I'll post TNs and link them here once I have some time.
1970 Taylor Fladgate Vintage Port - 96 points (****)
1980 Graham Vintage Port - 92 points
1985 Graham Vintage Port - 95 points
1975 Kopke Colheita - 95 points (***)
1977 Rocha Colheita - 97 points (*)
1994 Quinta do Infantado LBV - 88 points
1996 Quinta do Crasto LBV - 92 points
1991 Quinta do Panascal Vintage Port - 90 points
Several of the Ports moved significantly for me over the course of the night, the most notable being the '70 Taylor. That was the first Port we tasted, and at the time I gave it a quick 92 with a note to re-check over the course of the evening. That 92 is crossed out, as are the 93 and 95 that followed it, leaving only the 96 at the end of the night. It just kept getting better.
The Graham '80 started at 90 for me, briefly climbed as high as 93, but I finally settled on 92. I was wrestling with its tannins and heat as well as a slight bite in the late palate and early finish, and when that never really integrated I dropped it back to 92. I think it will probably get better with more time - it was the darkest Port of the evening, besting even the '91 Panascal.
Moving in the opposite direction, the '94 Infantado started out strong for me at 92 but seemed to me to become disjointed as the evening progressed. It also seemed like a very different style to me - much dryer than I'm used to, with much brighter fruits that I would expect in a 16-year old LBV. But rather than mellowing with air time, those bright fruits seemed to loose their fruitiness and age backwards toward under-ripe. (I started to say green, but that has an entirely different connotation.) I left it at 88 by the end of the night mostly because I think I just didn't really understand it and so was afraid that rating it lower would be unfair. It's tough to rate a Port that isn't at all your style.
Dom wins quote of the night with this one, refering to the 1975 Kopke Colheita: "It's like pecan pie on steroids." And you know what? He was right.
A few pictures:

Lisa, Vic, Kris, Melanie, John, Glenn, Roy, Dom, Markus

Lisa, Vic, Melanie, John

Roy, Dom, Markus, Kris

back row: '94 Infantado LBV, '96 Crasto LBV, '91 Panascal VP
middle row: '75 Kopke Colheita, '77 Rocha Colheita
front row: '70 Taylor, '80 Graham, '85 Graham

my first attempt with an Ah-So seems to have worked just fine!