Rarely does the phrase "all-reprint issue" get one excited, but when a package is put together as cool as this, it doesn't matter that you've read these stories before!
It was a great idea for an 80 Page Giant, to run all the new member-issues all together, and Neal Adams' cover is about as good as you can get.
The stories: "Doom of the Star Diamond!"(JLA #4), "Menace of the 'Atom' Bomb!"(JLA #14), and "Riddle of the Runaway Room!"(JLA #31) by Gardner Fox, Mike Sekowsky, and Bernard Sachs.
Roll Call: Superman, Batman, Wonder Woman, Aquaman, Flash, Green Lantern, Martian Manhunter, Green Arrow, Atom, Hawkman
Notable Moments: Hey, who's that weird green guy next to Aquaman? Oh! It's founding member the Martian Manhunter! Kind of like skipping high school all year then showing up for yearbook photos.
As I said above, the cover by Neal Adams is a classic--fun and celebratory; it makes it really feel like the JLA is a family, and that being asked to join that family was a Big Deal. In fact, the cover was so well received it's been homaged by no less than Gil Kane and Jerry Ordway...