I believe attention to how you drive the first few hundred miles will make a difference in how healthy the motor is down the road. A few dos and don'ts:
--No cruise control for first few hundred miles (point: always vary RPM)
--Avoid freeway trips the first couple hundred mi, but if you do, vary speed continually
--Give it a good workout after you get a couple hundred miles but don't abuse it.
--Don't totally baby it the first couple hundred miles, taking some quick runs accelerating to freeway speeds and back down are good.
--Don't let it idle, shut it off when you stop, and wind the motor up and down (ie 1000-2000rpm) while you wait at traffic lights (I did this, people probably thought I was a bit odd).
For the first tank I suggest urban cycle driving with lots of stop and go, that gives the components a variety of speed, load, RPM, etc. without hurting anything. Mix it up with jackrabbit starts, do not try to drive too efficiently. . . expect bad mileage on your first tank or two. I only got 15 then 17 on the first two tanks of my '03 2-wheel drive shortbed, which eventually became 20 on the highway at 80, 22 @ low 70s.
Vaughn