It doesn't seem like five minutes since BMW plonked the Concept 6 Series Coupé on a stand in Paris and said "there!"

So the appearance of a fully developed 6 Series Convertible, with an exact release date and everything, seems quick. But here it is: 24 March 2011.

This time BMW is going to town on its luxury credentials rather than wasting time trying to pretend it's a sports car. The cloth roof is carried over, multi-layered for refinement, but all talk from Bavaria is of a bigger, more luxurious car.

There are two engines from launch, both petrol. The 640i is a 3.0-litre turbocharged straight-six with 316bhp, and the 650i a 4.4-litre turbocharged V8. The latter hits 62mph in five seconds dead, while the former returns 35.8mpg economy. They're the headline figures.

BMW says this is the most highly specified 6 Series ever, with leather, navigation, Drive Dynamic Control, an eight-speed auto, xenon headlamps and parking sensors standard. For once you'll not need the options list.

But if you do choose to take a peek at the extras you'll see all manner of goodies including active damping, a full colour head-up display and softer nappa leather.

The car is also the recipient of the world's first Bluetooth-enabled in-car email reader thingy, for when that cheap Viagra offer just can't wait.

Space is increased in every direction compared to the current Six, which will be felt most in the back, and the boot increases to 350 litres with the roof up. Roof down it's 300 litres - only a little smaller than a family hatchback's.

No word on prices yet, but expect the entry-level car to cost about £70,000.

Mark Nichol - 18 Nov 2010