The Green Bay Packers can clinch an NFL playoff birth with a win plus a New York Giants win with strength of victory tiebreaker over the New York Giants. What does this mean?
It means that the team whose wins have come against teams with the higher combined winning percentage wins the tiebreaker. In other words, whichever team has beaten the teams who have won the most games.
Don’t we already know which team between the two has beaten the teams who have won the most games?
Sure, so far. But some of those teams could still win another game, and depending on which of those teams win and which lose (say, if all the teams only the Packers played win, and all the teams the Giants played lose), either team could still have the stronger strength of victory. That’s why you have those scenarios where the Giants need a Vikings loss OR a Lions loss or bla bla bla.
Not really. It will also depend on a number of outcomes tomorrow. Including Carolina, Atlanta IIRC along with 1 - 3 other games. It’s a PITA to try to explain. I’m just hoping we beat the Bears and look forward to Favre’s return next year. 
This is everything that has to happen for the Pack to get into the playoffs on the strength of victory tiebreaker. I wouldn’t count on this scenario playing out. But I would love to bet $20 in Vegas on the off chance it does. The odds must be incredible.
*Arizona wins at San Diego;
*Detroit wins at Dallas;
*Miami wins at Indianapolis;
*Minnesota beats St. Louis;
*San Francisco wins at Denver;
*Carolina loses at New Orleans;
*Houston loses to Cleveland
*Tampa Bay loses to Seattle.
And of course the Pack beats Da Bears which may be the longest of those odds.
But can’t any of those be ties?
As I read it, any one of these is allowed not to happen (if Detroit and Minnesota win) and GB will advance. Two or more and they’re out.
For the Packers to win on strength of victory, EVERY team the Pack beat must win tomorrow (except, of course, the Bears), and EVERY team the Giants beat must LOSE tomorrow (except, of course, the result of the Philly/Atlanta game, which is moot because they both lost to NY). That would give teams the Pack beat 53 wins and teams the Giants beat 52 wins.
If the Packers and the Giants tie on strength of victory, the next tie breaker is strength of schedule (combined winning percentage of teams played). Here, the Packers have slightly more leeway: without going into the combinations, the Packers can end up as many as three wins ahead of the Giants on this stat. And the games involved aren’t that farfetched (New England over Tenn., for example).
In my humble opinion, it’s the Detroit v. Dallas game that dooms the Pack, though I suppose the Arizona v. San Diego game is a bit tough to imagine the Cardinals winning, either. And some might say that seeing Chicago lose will be a bit surprising. 