This is a big beast of a car. That should be no surprise as the new car will likely be based on the 7 Series platform. A close look shows blue BMW M calipers hidden beneath the wheels. The front bumper has large air intakes that feed into the engine bay and brake ducts. The lack of quad exhaust tips means this could either be an early prototype or just an 8 Series with the M performance package, similar to the BMW M240i and BMW M760i. It's hard to discern without a closer look.
BMW hasn't officially announced a new 8 Series, so full details won't come out for a while. If it is indeed 7 Series based, look for a lineup of turbocharged engines, ranging from 4 to 12 cylinders. All-wheel drive is almost certainly a given on non-M models, but don't rule it out for an M8 as well. Look for official news as soon as this fall.