"The M3 Convertible will be powered by the same 420 hp, V8 engine used in the Coupe version unveiled earlier this year. For the US market it is expected to be priced around $55000. The 6-Series facelift will probably be unveiled this year at Frankfurt Motor Show. It will be powered by a V8 engine with output between 258 and 367 hp for the M6..."
This is from a new article on the BMW M3 Convertible and 6-Series facelift, from Topspeed, featuring brand new spyshots / wallpapers on these models.
You can read the whole article here: BMW M3 Convertible and 6-Series facelift - spy shots - Top Speed