They are going to bring out a diesel in the R8 soon, though it must be said i'd much rather take the V8 or the upcoming V10 (or the upcoming McLaren or Mercedes, whoever is making it). I think a slightly tuned version of the 4.2TDI in the Q7 makes more sense. Having a V12 might make the Lamborghini look a bit pointless (though i'd still rather have a Lambo), because some people won't see past the V12... Also, having a choice of 4.2L engines makes sense to me. 4.2FSI and 4.2TDI ? Ah well, we're about to get the 3.0TDI in the Q7 which is meant to be a corker of an engine.