"Open" is what the betting line was when betting on the game began. "Today" is what the line is now. "O/U" is the over-under.

Look at the second game, Carolina vs Atlanta. The line opened at 4, meaning Carolina is favored to win by 4 points. The line is now 3 1/2, meaning the bookies have had to adjust the line down because too much money was flowing to the Carolina side of the ledger, and they wanted more bets to come in on the Atlanta side. The over/under is 37 1/2, meaning bookies are guessing that a TOTAL of 37 1/2 points will be scored in the game. That's a total of both teams' scores. So, if you're a betting man (or woman), and you think Carolina is a lock to win this game, your friendly neighborhood bookie will take your bet if you agree to give Atlanta a 3 1/2 point head start. If you think it will be a low-scoring game, you can take the under, betting that fewer than 37 1/2 points will be scored in the game. If you think it's gonna be a shoot-out, take the over (more than 37 1/2 combined points in the game).

In the Green Bay game, "NL" (no line, or what we call a "pick 'em") means the books started at even, no one gets any points. Now the line is 5, meaning lotsa folks liked that line and bet heavily on San Diego, the favorite, so the bookies had to move the line to 5 and entice more bettors to put their money on Green Bay to even the books.

As long as the amount of money is roughly the same on either side of the books, the bookies make money (due to the vig, or the juice, which is the "commission" they get for taking bets (generally 10% of the bet). They don't care who wins, they just want their books to balance so when they pay off the bets, they can dip from one side to pay the other without touching their vig, which is pure profit.

What all this tells us about the Packers this week is that they are a 5-point underdog against San Diego, but they started ouit EVENLY MATCHED. That's important: that means the oddsmakers shrugged and went "we have no clue". That the line moved reflects not on the quality of the teams but on the state of the books: bettors thought San Diego was better on paper than Green Bay. But 5 points! That's less than a touchdown, and I'd take that bet, given the way Philip Rivers is stinking it up and Brett Favre is not.

So, to summarize: San Diego (-5) means the same thing as Green Bay (+5), and the O/U is the total of all points scored in the game. None of these numbers reflect anything about the teams' actual performance to date, remember: they're just a way to show how the gambling money is flowing. They're a representation of thousands of bettors opinions, nothing more.

Thanks! That was an awesome explanation! And I'm glad to see those bettors may be wrong, as we're currently leading, 17-7.

go pack!

Yay, Ur Stillers are kicking SF's but!

That, BitterOldPunk, was elegant.

Thanks! I messed up, though. When I said, "...the bookies have had to adjust the line down because too much money was flowing to the Carolina side of the ledger, and they wanted more bets to come in on the Atlanta side", I got it precisely backwards. Reverse "Carolina" and "Atlanta" in that phrase and it makes sense.

odds, shmodds. We won!!

.....and San Diego didn't cover the the spread. So it's like they double-lost.

Gah! I give up on the Chargers this season. You're on notice, Norv Turner!

Full disclosure: the Chargers were my pre-season AFC Super Bowl pick. Oh, well.