1.) The Steelers running attack is highly successful, and is what killed the Chargers. The Chargers have a better run defense than the Cardinals (the only reason they kept Carolina's running yards low was because they had such a huge lead, it forced Carolina to pass).
2.) Whisenhunt does not know the Steeler offense. The Steeler offense when he was there was the power-I running attack. Bruce Arians brought in the single back balanced attack. What Whisenhunt DOES know is Ben Roethlisberger. He may know how to get in his head, but that was 2 years ago, and Ben has matured greatly.
3.) If the Cardinals put 7 in zone, Parker will run all over them. If the Cardinals attack the run, Ben will pass off of play action. This is why balance is more powerful than a strong passing attack and no running game (a la the Cards).
4.) Look at last year. No one was capable of beating the Patriots. They had a spread formation with two of the best WRs in the game. Sure, the Giants had a good pass rush, but they didn't have the secondary to match up.... sound familiar? Defense wins championships.
5.) Larry Fitzgerald. Yeah, the kid is good, but Dick LeBeau is GREAT at taking away the best receiver. Ever heard of Chad Johnson and TJ Howsyermama? Chad Johnson notoriously caught 1-3 balls those games for like 17 yards. The Steelers face good WRs all the time and know how to shut down the passing attack. They are #1 against the pass, ya know...
The keys to the game:
For Pittsburgh: Willie Parker. If he can get going, the Cardinals will be doomed. He is JUST now healthy, and in this offense last year, he lead the league in rushing until he broke his leg late in the season.
For Arizona: The offensive line. If that offensive line can't handle the 34 (as shown by the game against the Pats), the offense won't score but field goals, and that's if they can get the ball in range.
The Cards won't break 30 points this game, and I don't think their D is good enough to win it for them.
Cardinals 20, Steelers 32.
One last thing:
If Arizona comes out and scores on the first drive, its one of the BEST things that can happen for Pittsburgh. Everytime that's happened, Dick LeBeau has adjusted the defense and prevented scoring for most of the rest of the game.