Posted by carscoops.com, the still heavily disguised prototype does not reveal much in terms of styling aside from a wide front apron and air intakes, with the biggest speculation being its choice of engine and possible switch to all-wheel drive like the new M5.
Due to ride on the same CLAR platform as the 5 and 7-series, reports are that the M3 could be powered by an upgraded version of the current S55 3.0-litre twin-turbo straight-six, or even feature a mild-hybrid setup similar to Mercedes-AMG's new line of 53 models.
With the new 3-series expected to go on sale next year, the M3 is reportedly set go to hit the market in 2020 but not before making its alleged world debut at the 2019 Frankfurt Motor Show.
..and the X5 M

In addition to the M3, carscoops.com have also spotted the all-new X5 winter testing, albeit in M guise sporting what appears to be a redesigned front facia, new headlights with integrated daytime running LEDs, fat dual exhausts and blue brake calipers.
In standard spec, the X5 will also make use of the CLAR architecture, which according to the article, will shave some 300 kg off the existing model. In M form, the X5 will likely use the same 441 kW 4.4-litre twin-turbocharged V8 as the M5, which could lead to a 0-100 km/h sprint of under four seconds.
According to the BMW Blog, the new X5, which will be replaced by the X7 as the new flagship BMW SUV in 2019, will make its long awaited debut later this year and offer a selection of four and six cylinder turbo-petrol and turbodiesel engines mirroring those of the 5 and 7-series, as well as a V8 petrol. A plug-in hybrid will also be offered with a eight-speed Steptronic gearbox likely to be standard on all models.