Good news and bad news go hand-in-hand, but in this case, it's not entirely unexpected.
According to Audi RS6 project manager Jens Koch, the twin-turbocharged V10 sedan won't be coming to the U.S. in its current iteration. Originally, Audi thought that the four-door body style would be more appealing to Stateside consumers rather than the Avant, but apparently there's too much energy and expense involved in making the V10 powerplant pass the more stringent sniffer standards here in the U.S.
On the upside, the third-generation RS6 is being developed for the global market, so the next iteration should arrive on our shores in 2012. Koch hinted that the RS6's weight problem and 5.0-liter V10 wouldn't carryover to the 2012 model, and that the next RS6 will be more "revolutionary" and "far more RennSport than anything previously developed."
Meanwhile, Audi will take the wraps off the RS5 this January in Detroit, with the next RS4 debuting shortly thereafter.
Audi plans to further its goal of taking on BMW's M division and Mercedes' AMG lineup with more Quattro-branded vehicles positioned above run-of-the-mill Audis, along with more clearly defined R-, S- and RS-derivatives. "S" badged variants will also be sportier than current S models, while the "R" lineup will be "significantly souped-up" and "RS" will be reserved for lightweight, track-friendly models.