I think the issue is whether you intend to own the truck outside the factory 3/36 bumper to bumper. If so, then you're "Self-Insuring" on everything other than the drivetrain -- which is the strongest aspect of these trucks anyway.
On my 3rd gen, after I got past 3 years, I replaced my AC compressor, blower motor, evaporator, turn signal switch, driver door electric lock, and other stuff I can't even remember. All on the $1200 MaxCare 7/70,000 plan with $0. 00 deductible AND free rental car. I just cancelled this contract when I got the new 2010 AND am (get this) entitled to a $518 partial refund as the truck is 5 years old with 43,000 miles. They don't consider how much they paid out ($4k) in repairs when calculating a partial refund.
You bet I'm getting the same plan on this 2010, buy it online at a great discount and enjoy the free rental car for maintenance until the plan kicks in after I'm out of warranty.
So my point is, although I'm generally against extended warranties, this is a special case and really depends on whether you're going to be owning outside the 3/36,000. The drivetrain is the least of it, IMHO.
Good luck!