Question on upgrade & V8

[gsportiva]

You know the M3 recently inherited the updated iDrive2 and LED rear lights from the new face lifted 3 Series.

How come it didn’t get the new LED’s that are in the front of the new 3 Series headlights?

Would you consider this just a minor upgrade or a facelift?
I'm thinking upgrade...

When BMW was creating the new V8, I know they new that adding direct injection was going to be good for things like fuel economy and performance, does anyone know why they omitted it?

Companies like Audi, Porsche are now adding it but they are adding it on engines that were not done right from scratch.
Was it a cost issue?

Does adding direct injection on an engine make it heavier… or just more complicated?

Do you think that there is the slightest chance that they could incorporate direct injection in the future in the V8 or the next M3 will be a turbo inline 6 with direct injection… is this the first and last consumer V8 to be put in an M3 due to meeting emission standards?