That is what I call very clever marketing !
The Audi guys really rock, including Audi's marketing. While it is logic to use the WEC and Le Mans platform to communicate about Audi's upcoming range of "e-tron" models, combining it with the well-known "quattro" designation that is strongly associated to Audi's sport heritage (and current car branding) is very clever.
This being said, the "e-tron quattro" designation may be somewhat confusing.
Up to now, I believe that the "e-tron" designation was mostly used in connection with Audi's fully-electric concept cars. I do however recall that Audi recently presented an Audi A1 e-tron concept with a small electric motor delivering power to the rear axle in addition to a conventional combustion engine delivering power to the front axle (or am I wrong ?). Interestingly, but logically, the R18 e-tron quattro works the other way around
As regards the "quattro" designation, the R18 e-tron quattro is clearly not a true AWD car since power is separately delivered to the front axle for a relatively short duration, and only above 120 km/h.
This being said I am again eager to see this car in race conditions and how its compares to the "normal" R18 "ultra".