1/12 scale and lipo
The biggest problem I see in 1/12 scale is the same problem as in 1/10 scale, people are trying to find equivalent motors and batteries in lipo and bl as for nimh and brushed. This is simply not going to happen.
Winding a bl motor at 21t is not that different than wiring it at 13.5 turns, the wire is thinner and there is more of it, that's the difference. Brushless technology doesn't lose its inherent advantages because the motors have more winds and are slower. In terms of lipo for 1/12, 7.4v is fine, but you need a slower motor. For batteries, take a look at the r/c plane and helicopter market, they have plenty of 2 cell lipo packs that would fit into any 1/12 scale that can use a 4 cell straight pack (not split pack.) In terms of the motors, a lighter 540 brushless motor would work fine. The only thing to add would be some weight under the lipo pack to maintain the weight balance of the car.
All of this can be done today with existing products. The only thing holding everything back is the search for equivalency.
Trackpower, are you 14 yet?