The Highlander is essentially the same for 2007, save the addition of new headlights and more standard safety features like side and side-curtain airbags.  There are several variations of Toyota's mid-size SUV, due to an interchangeable selection of engines, drive trains, and trims.
The Limited offer the most upscale finish.  This model adds heated mirrors, a wiper de-icer, automatic climate control, an eight speaker JBL sound system with an in-dash CD changer, wood trim, and a third row of seating.  All models come standard with air conditioning, full power accessories, and keyless entry.  The Limited is only Highlander which is eligible for the navigation system.
The Limited trim is available with both 2WD and AWD, but no four cylinder is offered.  The only engine option is the larger 3.3 liter V-6, mated to a five speed automatic transmission, and enhanced by Variable Valve Timing + intelligence technology.   The VVT-i system manages the intake camshaft for better power, efficiency, and emissions control.  The 215 horsepower Highlander receives an EPA estimate of 19/25 mpg, and it earns SULEV emissions rating.