The 2009 TSX has a wheelbase that is 1.3-inches longer than the current model and gets an extra 2.4 inches in overall length. The model is also the first from Acura to make use of inside frame rails, which are design to improve underfloor aerodynamics.

The in-dash iPod interface lists track, album, and artist information and provides drivers with a straightforward means of browsing tracks.

Structural updates to the TSX include the closed-channel cross-braced roof structure for greater rigidity, a stronger rear bulkhead, and new A-, B-, and C-pillar separators to improved noise and vibrations at high speeds.

For iPods connected via the USB port, the TSX has a dedicated interface based on the menu structure of the iPod itself. Using the rotary control knob, drivers can navigate Apple-inspired categories.

Above the rotary jog wheel, the navigation-enabled TSX features a large Map/Guide button, which gives drivers a useful one-touch means of getting back to the navigation screen.

Like other recent Acura models, the new TSX features a central console packed with a barrage of controls for the navigation and audio systems. The design improves upon earlier versions with the addition of a prominent power-volume knob, letting drivers turn the stereo volume up or down without having to hunt around for the relevant button.

The 2009 TSX is also available with Acura's XM-sourced real-time traffic information service, which to date was optional only on higher-end models. This updated version of AcuraLink features dynamic route guidance, which proactively suggests alternative directions when traffic is detected on the current route.

The AcuraLink weather service uses XM's "Threat Matrix" technology to track nationwide weather information for more than 20 different weather conditions, then scales and customizes this detail to the driver's location and route.

However, a look outside would have told us the same thing, and on our test drive the AcuraLink weather system had failed to warn us in advance that there would be a snow storm on our route, meaning that we got trapped in blizzards for hours. Not the most auspicious of starts for the new service.

On our test drive of the 2009 TSX, our weather-enabled navigation system told us that there was snow in the vicinity of our route.

The TSX gets a seven-speaker sound system, Acuras' Bluetooth HandsFreeLink phone interface, and a USB port for audio playback all as standard equipment. For audiophiles, the TSX is available with a 10-speaker ELS 5.1 surround-sound system, tuned by Grammy-winning sound engineer Elliot Scheiner.

The new TSX's "double plenum" nose treatment is in keeping with Acura's modern design language, which tends to give its cars a sharpened, beaklike front end.

The 2009 TSX is available with either a six-speed manual--complete with short-throw shifter--or a five-speed automatic gearbox, which can be activated using steering-wheel mounted paddle shifters. According to Acura, the manual transmission makes use of "performance-oriented ratios" for Second through Sixth gears, while the the Sequential SportShift automatic transmission features a new lock-up torque converter assembly.

The TSX becomes the second car (following the Acura RL) to get XM's real-time weather tracking system. Available as part of the TSX's Technology Package, the service is integrated into the navigation system and provides information in a variety of at-a-glance formats on weather conditions for the current route or for other parts of the country.

Touted by Acura as "larger, more agile and more powerful than ever before", the second-generation entry level TSX compact sedan is aimed at younger, tech-savvy customers.

As we have seen on other Acura models, the subscription traffic service provides useful detail on the nature of incidents on the current route.

Despite Acura's claims that the new TSX is more powerful than its predecessor, its 2.4-liter direct-injection four-cylinder engine gets four fewer horsepower than the current model, delivering a still-respectable 201 horsepower. Torque is increased to 172 foot-pounds, however, and the TSX gets an improved ULEV emissions rating from the California Air Resources Board.