Most of the range will appear a year earlier, this September, following on from the 7-series and Z4 with an unusual and potentially risky new look. However, design chief Chris Bangle and his team have avoided repeating the awkward proportions and odd rear-end treatment of the flagship 7-series. The new 5 is clearly a more smoothly-integrated design than the 7, but the unusual headlamp and tail-lamp clusters and 'beaky' nose will take some getting used to.

At launch there'll be three variants, all with straight-six engines. Two are bi-VANOS-equipped petrol units: the 170bhp 520i (9.0sec 0-62mph, 143mph, 31.3mpg) and the 231bhp 530i (6.9sec, 155mph, 29.7mpg). The 530d is powered by BMW's highly-regarded 3-litre straight-six turbodiesel. This unit has the second-generation common-rail injection technology and is good for 218bhp and a hearty 369lb ft of torque. It can sprint to 62mph in 7.1sec, hit 152mph, and still average 40.9mpg.

A couple of months later, BMW will launch the 520iA (192bhp, 2.5-litre) and the 545i. The latter is powered by a new Valvetronic 333bhp/332lb ft 4.4-litre V8. A new six-speed manual 'box is standard on both cars and a six-speed auto is optional.

Inside, the family feeling established with the 7-series has been retained, as has the controversial iDrive controller. However, BMW has moved to improve the safety aspect of the system by modifying the controller and screen. More significantly, the 5-series can be specified with a head-up display. The driver can select information of his choosing - including navigation instructions - and have it projected onto the windscreen.

Improvements in performance and economy have been helped by the lightweight construction of the E60. BMW says the car has the highly unusual combination of a high-strength steel monocoque and a 'lightweight aluminium front section'. Depending on the version, the 5-series is up to 75kg lighter then the outgoing model, despite being slightly bigger than the old 5 and offering rather more rear-cabin space and a much bigger boot.

Aluminium has also been used for the whole of the chassis and suspension set-up. This is not just a general weight-saving device, but also greatly helps chassis performance - particularly ride. This is because it reduces unsprung weight, allowing the suspension to react quicker to the road conditions.

But it's in the 'intelligent' electronic systems that BMW has really stolen a march on the competition. The most outstanding innovation - already tested by evo - is the optional Active Front Steering (AFS). This system varies the gearing of the steering depending on the conditions. At lower speeds and in bends it is more direct, making the car more agile. At high speeds it becomes more indirect, greatly improving directional stability, especially during emergency manoeuvres or lane changes. AFS is networked to the Dynamic Stability Control (DSC) so it can adapt rapidly should the car become unstable.

Also in tune with the steering and DSC sensors are the optional Active bi-xenon headlights which are said to swivel in 'real time' to illuminate bends in the road ahead. Also new is the Brake Force Display which BMW claims will reduce bumper-to-bumper collisions. The harder the driver applies the brakes, the more of the brake light area is illuminated, providing a warning to following drivers. It is still being homologated for European roads. Radar-based Active Cruise Control is an option on the car and run-flat tyres will also be available, completing the safety package.

Prices have not been revealed, but they are not expected to increase greatly over today's 5-series.