What oil should I use in my 03' RS6 and how many quarts?

I've searched this board and I can't find a definite answer. I do know the Audi/VW part number for the oil filter is 078 115 561 K.

By the way, what kind of oil is it that it can go 10k between changes, but other synthetics have a recommended 3k change interval?

Thanks,
Chris