The 3.5L V6 engine is carried over from the prior model, but in a nod to a more fuel-conscious America, a 2.7L I4 engine is added. Moving power to wheels is a new six-speed automatic transmission, which replaced the prior five-speed. While most production is front-wheel drive, Toyota continues to offer all-wheel drive with V6--the only minivan to do so since Chrysler dropped AWD from their stable. Overall, the powertrains don't raise the bar.

Four-cylinder-motivated minivans have a grim history, and Sienna has not before offered one. Here the 187HP 2.7L Sienna felt adequate around town and at sea level, but I'd pick the 266HP V6 for Colorado! Trailer-tow capacity is listed as 3,500 pounds (as much as any minivan might need) and is for the V6 models only. Toyota's estimated EPA fuel-economy numbers put the I4 at 19/26/22 and the V6 at 18/24/20 (city/highway/combined, FWD models). Opting for the I4 will not mean substantial savings at the pump, but there is comfort in knowing you're using less fuel.

There are no less than five, count them, five models or series available, and I drove four of them. The model series stretches from the budget-oriented Sienna all the way to full-boat Limited, with a lowered and more aggressive-looking "sporty" SE thrown in the mix as well. And even the base Sienna takes cruise control, tri-zone air conditioning, power locks, remote keyless entry, power adjustable driver's seat, and power windows. The Limited brings smart key, independently operated sliding dual moonroofs, and power folding third row. As expected from Toyota, each looked appropriate inside and out. No buzzes, squeaks or rattles. Fit and finish was not perfect, but these were preproduction versions, and minor improvements were still being implemented.

Sienna's improved feature availability enhances comfort for all. The 2011MY, still offering seating for seven or eight, brings excellent long-slide middle-row seats and convenient-to-stow third-row seats. In the eight-passenger configuration, the middle second-row seat can also be removed and stored. The optional dual-view rear-seat entertainment system allows each child to have his own program--from the same screen! Who would have thought? This 16.4-inch widescreen can show a single program, easily viewable from both second and third rows, or the split screen mode optimized for the second-row. Second-row captains chairs on the Limited model both recline and have a Lounge Seating feature that gives passengers a footrest. Talk about comfort!

Both a regular angle and wide-angle backup camera view is available -- a real boost for minivan drivers. Other options include dynamic radar cruise control and a pre-collision system that senses imminent collision and tightens the seat belts and takes other safety precautions.

Both appearance and safety are enhanced with halogen projector beam headlights. HID (High Intensity Discharge) headlights are available on selected models and provide brilliant illumination and a cool, contemporary exterior appearance. While cornering headlights are not available, the HID lights do have an auto high-beam feature.

The voice-activated touch-screen navigation system is easy to operate and useful in the congested driving conditions. The rain-sensing windshield wipers, on the other hand, my not get much use here in Southern California. In areas with more variable weather, they are likely to be highly appreciated.

Despite being a shadow of its former self, there is tough competition in the minivan market. In this environment, I think Toyota has provided a new King of the Hill. On sale in February 2010 (the I4-equipped Sienna arrives in April), customers will soon have the chance to vote with their wallets.