It's quite clear

Unfortunately, the VW Group's new seven-speed dual-clutch automated manual (called S tronic by Audi) will not be offered in the U.S., as Audi feels Americans prefer the smoother shifts of a conventional torque converter.

It's as simple as that.

Also,

Discussion continues in Ingolstadt as to whether to offer a diesel in the future. Johan de Nysschen, head of Audi of America, is pushing for diesel in the Q5 rather than in the Q7 for the U.S.

Diesel Q7 makes more sense imo.<ul><li><a href="http://www.caranddriver.com/news/auto_shows/2008_beijing_auto_show_auto_shows/production_debuts/2009_audi_q5_auto_shows">Car and Driver about the Q5</a></li></ul>

no 3.0L TDI, no sale here. I will move on to BMW or Benz who will already have diesels on the market by the time of Q5 launch.

ML, GL, and X5 are not the same as the Q5. None of the bigger competitor diesel SUVs will get much better mpgs than the gas Q5. More barrels of oil/green house gases for them as well if you really care about that.

The Q7 TDI should launch about the same time as the Q5. 25 mpg highway for the Q7 TDI.

...I may be in need now of something that can haul a small or medium size trailer, nothing outrageous that needs a Cummins, but the 3.0L TDI would be perfect for this. A Tiptronic might be better for towing purposes.

...I'm sure there would be a problem with how the US rates torque converter less transmissions for towing.

number of vehicles sold is greater than the Q7. Hence, the number of diesels should be higher.

In reality, the A4, A5, A6, A8, Q5 and the Q7 can use the same 3.0 V6 TDI, so let's get them all over here!