Kevin Seifert took some shots for not ranking Lambeau Field as the toughest home venue. From ESPN:
In brief: Lambeau Field is a beautiful stadium with the potential for the coldest weather in the NFL. But its noise level doesn't impact opponents the way others venues do, and its field condition actually limits the home advantage, in my assessment.
As far as I'm concerned, Lambeau should be a model stadium in the design for all new football stadiums based on the design and location. As many perks as new Cowboys Stadium had while I was there for the Super Bowl (if you can afford it), I wouldn't have wanted to have gotten a (relatively) cheap seat up in the rafters. I'm sure the new Vikings stadium (in whichever city it's built) will have horrible cheap seats too. My good seat for the Super Bowl wasn't as good as the awful seat (end zone, near the top) I had on my last trip to Lambeau.
He ranked Qwest Field, Heinz Field, and Superdome ahead of Lambeau. It can get really loud at Qwest Field and the Superdome, and those stadiums are better designed at keeping the noise in than Lambeau. Unfortunately I can't say I've been to either for a comparison. If Heinz Field is ranked higher just because their playing surface is so incredibly awful, then I guess they can have that one. The surface at Lambeau was awful during the 1990s in late season playoff games, but they've done a lot to improve it over the last 10 years. Now they're willing to try concerts on the field too, depending on the amount of damage it caused. I'd much rather the stadium have a good playing surface, making for better games, then manufacturing a home field advantage.
The toughest place to play is always on the road anywhere against a great team. The greatest of Lambeau is one thing, and how tough it is for visiting teams is another.