The 2010 BMW Z4 has officially been revealed. Click here for all the details and images.

BMW’s next-generation Z4 Roadster is due for its first public outing at the 2009 Detroit Auto Show, but the new spy shots have revealed the car about a month ahead of the show. As hinted at by the spy photos and confirmed with the newly leaked images, the car features fewer Bangle-born styling cues and a smoother, more rounded appearance than the outgoing version.

Contrary to numerous reports the new model is expected to grow in both size and price. The new Z4 is tipped to receive a folding metal hardtop to bring it into line with the Mercedes Benz SLK and Mazda MX5 (Miata). For BMW, the benefits of the folding hardtop (security and reliability) outweighed the disadvantages of increased weight and less trunk space. However, there is also the possibility that both a hard-top and a traditional soft-top could also be offered.

Throughout the car's development, styling was expected to feature cues derived from the CS concept including a wider and more pronounced grille and larger intakes up front. Though the final product doesn't seem nearly as extreme as the CS Concept, there is a hint of the controversial design in the new Z4.

A long hood and a short rear decklid remain but the previous car’s circular taillights have been swapped with units that appear similar to those on the larger 6-series with including rows of LED detailing.

The engine lineup should include both twin-turbo and naturally-aspirated straight six engines, although there could be an entry-level model in Europe with a four-cylinder mill, though that won't be due until sometime around 2011. The naturally-aspirated six-cylinder is expected to be rated at about 272hp (203kW), an upgrade of 17hp (12kW) over the current sport model, while the flagship M Roadster - if it is built - is likely to get a brand new high-performance turbo six worth around 350hp (261kW).

This is to ensure the M-spec Z4 doesn’t step on the toes of the M3. The Z4 range is also expected to pick up BMW’s new 7-speed dual-clutch transmission as an option. A 6-speed manual will be standard.

With more equipment and a bigger powerplant, pricing is expected to rise to about €43,000 ($55,000) in Europe. The Z4 currently starts at around $36,700 in the U.S., but that can be expected to climb past $40,000 for the next model.

2009 BMW Z4 convertible