Would not surprise me if the Pack lose in the Glass Menagerie - I saw George Strait there in January (I think) so, henceforth, the Glass Menagerie shall be named George Strait Stadium.
That tidbit being introduced into evidence ... I'm going to qualify your prediction of defeat and I'm sure you wouldn't have made such a heinous statement without first putting new batteries in your crystal ball but here goes. Vikies have an entirely new coaching staff and a new scheme to go with it. Cousins is not a dumb man, so he's probably worked that playbook and has it down-pat. Cook and Jefferson are Pro-Bowl professionals and should make the transition well enough. O-linemen are usually the smartest and best looking fat guys on the field - so, they'll have those blocking schemes committed to memory and will execute said offense like Napoleon's army.
Defensively, the Vikies have dumped their 4-3 scheme in favor of a 3-4 - personally, I see that as six of one and a half dozen of the other, the defenses are usually ahead of the offenses this time of the year even if the preseason saw starters getting up to game speed.
Green Bay on the other hand had a coaching staff get totally out coached to lose a trip to the Super Bowl which I'm sure they'd have won because dreams and what if's and stuff should never be discounted when speculating and talking cr*p. The wild card here is Green Bay's coaching staff is pumped up to prove that they're NOT the Gang Who Couldn't Shoot Straight and prove all of the nay-sayers wrong.
Thus, the Packers will beat the Vikings at George Strait Stadium by one-half of one point which includes the 3 pts that the home team gets just because they didn't have to travel.
Now just in the interest of full disclosure, I want you to know that MY crystal ball doesn't run on batteries anymore. I found a YouTube video that showed me how to soup up my crystal ball to run on a nuclear powered generator. So ... be very afraid. I GOT THIS MAN.
Let us not become nattering nabobs of negativism so early in the campaign.