Apparently so. According to the information on Amazon.com, this little box contains every issue from 1970 to 1998. It’s not clear whether special issues (the Yearbook Parody, Encyclopedia of Humor, Very Large History of Comics, etc.) are included.
I was very surprised to learn of this (thanks to Brian for the tip). I was under the impression that the copyright issues surrounding the magazine would have prevented this. But apparently a recent court ruling concerning National Geographic putting its back issues on DVD made it possible. There was a short item about it today on Boing Boing.
In any case, I think it’s great news for NatLamp fans, who can now peruse through every issue of the magazine for fifty bucks. (Nothing beats the real thing, though, what with all the printing tricks and different paper stocks they used for the sake of a joke.)