2 + 2 + 1, here.
The real issue, for those with youngest children, is the permanent attachment of child restraint seats to the LATCH hooks or via seat belt. Of course, this precludes flipping the outer seats.
Further, most kids prefer space between them rather than sitting in two adjacent positions. This means the center section is left open (although it's arguably the safest place for a child seat). Also, using the center seat for little kids in forward facing boosters or car seats places their sweet, muddy shoes on the center console vents, so it's not really optimal from a functional or maintenance standpoint.
We have our 18 mo. old rearward facing (attention -- keep 'em that way until 2 yrs, see 2008 study from WI on skeletal development and safety!) behind the passenger, the 5.5 faces forward (five-point harness in a Radian by Sunshine Kids, way mo' better than booster!) behind the driver.
Middle row center is down and sometimes in lowered position, but ready to raise for an adult.
A spare booster resides in the pass. 3rd row seat for carpool or friend duty. This visiting child crosses over the middle, followed by a parent's arms that safely buckle her in back there. This is easy since the female buckle resides towards the middle of the car. In contrast, the middle center seat female seat belt buckle is on the right side of the seat cushion and so gets hidden between the booster and the rear-facing seat making it very hard to see and reach to buckle while crouching in from the middle row driver's side and practically impossible to use from the passenger side with a rear-facing seat in place. This is why the middle row center is our extra adult seat and the passenger rear our spare kid seat.
We who never off-road our trucks all really need minivans, vehicles that go 50% further on a gallon of fuel and maximize passenger space within the envelope, but my wife is not buying that argument just now when we both so enjoy her LR3.
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