BMW today released initial details on the 2007 3-Series convertible, which will go on sale early next year. The car will make its debut at the Detroit auto show in January. Like its coupe counterpart, the cabriolet will be offered in both 328i and 335i editions in North America, and 325i and 335i guises in Europe. BMW says the 306 horsepower 335i model will reach 62 mph in 5.8 seconds.