So far, we have a handful of images showing exactly what you'd expect, namely, a two-door take on the current F30 3-Series. Alternately, it's the production take on the 4-Series Coupe Concept. Either way, the end result is the same: a whole lot of familiar tucked into a new shape.
According to the info leaked so far, we can expect the 4-Series to come in both 428i and 435i forms, meaning both turbocharged 2.0-liter four-cylinder and turbo 3.0-liter six-cylinder engines will be offered. Power output should be unchanged from the 3-Series offerings, meaning 240 horsepower for the 428i and 300 horsepower for the 435i.
Beyond that, however, we're still largely in the dark--for a while, at any rate. No word on the possibility of an M4 has leaked yet, though it might not join the regular 4-Series launch anyway, instead waiting for its own debut.
Stay tuned later today, as we'll have the full and official details, photography, and more.

2014 BMW 4-Series leaked images