The Altima is arguably the most important Nissan product of the last decade. If you go back a mere 10 years and look at Nissan circa 1996 you'll see a company struggling to survive in the North American market. The Z was about to die. The "premium" products coming out of Infiniti were lackluster at best, and nothing in Nissan's future portfolio indicated a turnaround was anywhere on the horizon.

Fast-forward to the New York auto show — spring of 2001. Nissan rolls out an all-new Altima that offers more interior space, more horsepower and considerably more attitude than the former family sedan benchmarks from Honda (Accord) and Toyota (Camry). Can you say "shift-paradigm"?

Fast-forward another five years to spring of 2006. The Z-car is back, there's a full-size Nissan Titan challenging the domestic trucks, and the Infiniti G35 is openly threatening BMW's 3 Series. Yet the Altima's claim to fame remains the most impressive of them all: It is among the top five best-selling cars in the U.S.

Nissan obviously hopes to continue, and even build upon, the car's success with an all-new 2007 Altima. We were lucky enough to road test an early production model before the 2006 New York Auto Show unveil, and we have a solid picture of how the redesigned Altima will fit into this ultracompetitive segment.

All-new from the platform up
Starting with an all-new "D" platform, Nissan lowered the engine, upgraded the front suspension geometry and improved the shock absorbers for better steering response and handling. The new engine location allows the half shafts to be mounted at equal angles to reduce torque steer, while a new upper cowl structure provides increased rigidity at the front-suspension mounting points. The rear suspension continues to use an independent, multilink design and antiroll bars are mounted at both ends of the car.

Base Altimas utilize 16-inch steel wheels with 215/60 tires, but 17-inch alloys wearing 215/55 tires are available on the 3.5 SE models. The 3.5 SE also features a sport-tuned suspension and larger antiroll bars. Much of the 2007 Altima's improved rigidity comes via the use of high-strength steel throughout the platform, as well as a 1-inch-shorter wheelbase. Despite these structural gains the new model is only 55 pounds heavier than the current car.

With a proclaimed engineering target of creating "the best performing front-wheel-drive sedan in the world," we had rather high expectations for the new Altima. What we got was a noticeable uptick in steering feel and feedback and an overall sharper, more nimble car. The improved front suspension tuning, along with the new speed-sensitive, power rack and pinion steering system, provides a precise and linear steering response that rivals the class leader in this area — Honda's Accord.

Drivetrain developments
Adding to the Altima's fun factor is a more powerful 3.5-liter V6. Final SAE horsepower figures have yet to be released, but expect the peak number to come in around 265, a 15 horsepower increase over the current model's V6. Reduced internal friction and improved cylinder head cooling contribute to the increase in horsepower while also providing a more refined engine note. The base 2.5-liter four-cylinder gets a bump in compression ratio, an improved balancer system and a larger intake manifold, but final numbers for this engine are similarly pending.

More impressive than either engine is the new Xtronic CVT. This is the same unit found in the Murano SUV, but it has benefited from an upgraded "Sport" controller that uses adaptive logic to adjust shift patterns under varying conditions.

As a rule we haven't been too impressed with CVTs, but our brief experience in the Altima suggests this technology is finally ready for prime time. While technically not "shifting" at all, this CVT made the most of both the four-cylinder and V6 engines' power and torque. When rolling into the throttle, or climbing a hill, the CVT allowed the engines to rev quickly and build power before executing a simulated — and very positive feeling — "upshift."

Nissan has been pushing CVT technology for over a decade. It feels the improved efficiency and smoothness offered by this transmission design represents the wave of the future. The company expects to sell 1 million CVTs globally, every year, by 2008. If they all work this well we'll happily contribute to that number. Buyers still not sold on the merits of CVTs can select a six-speed manual transmission for either engine.

It's what's on the inside that really counts
While we appreciated the 2007 Altima's structural and drivetrain improvements, I think everyone can agree on where this car really needed a redo: interior quality. As paradigm-shifting as that 2002 Altima was, it never threatened the segment leaders in terms of cabin environment. For this redesign Nissan wanted to "build on the strengths, address the weaknesses" of the current model.

Tapping on the new Altima's dash and door panels confirmed Nissan did its homework. The previously rock-hard plastics have given way to…well, supple plastics. Seat leather and interior controls are also clearly improved. It's not like you'll confuse the Altima's interior with an Aston Martin's, but the car can finally stand toe-to-toe with Accord and Camry cabins.

For instance, our test car was equipped with dual-zone climate controls and the temperature ***** had a confident, weighty feel as we turned them back and forth (also a slick temperature display inside the *****). The gauge cluster and radio displays have a significantly brighter and more polished appearance, and the available Intelligent Key system allows for push-button engine starting.

Other options include a nine-speaker Bose audio system and a Bluetooth hands-free phone system. Of course there's still that Nissan-esque folding door over the storage pocket at the base of the center stack. But the one on our test car actually worked smoothly without feeling like it was about to break off in our hand.

It's also worth noting that although Nissan shortened the car's wheelbase by 1 inch during its redesign, the Altima's total interior volume remains the same. This was accomplished by reworking the firewall location and trunk layout, yet trunk space remains about the same.

All-new car, same old mission
Nissan wants the 2007 Altima to be among the top three selling cars in the U.S. Beyond the improvements listed above, the company will add a hybrid model during the winter of 2007 as part of its goal. These enhancements will probably maintain the Altima's standing in the market, but with an all-new Camry (and Camry Hybrid) hitting showrooms, along with increasing pressure from upstarts like Hyundai and Mazda, getting Altima on the sales podium will be an uphill battle.

Nissan doesn't appear concerned, however. The Altima has been part of uphill battles before.