Per SB Nation's NFL odds, the Falcons are 3 to 3.5 point favorites, depending on your source. Considering Atlanta's on the road, they're coming off a shaky win over Washington, and the Saints still have Drew Brees. That's good for a couple of points in Vegas every time out.
It's worth remembering, as well, that the Falcons and Saints usually have bitter, hard-fought battles that wind up being quite close. The Falcons should win this game, because this year's Saints team is a mess and likely the last gasp of the best run in the franchise's history, but the Saints will fight like hell and would love to spoil Atlanta's undefeated start. I can't imagine the Falcons will take them lightly, but it's not likely to be an easy game.
Let's hope the Falcons are 6-0 in a blowout.