This Racer article states Indycar is in talks with CoTA and other unnamed tracks as a possible replacement for Brazil, potentially joining the PWC weekend at CoTA. I can't really see it happening, as they already have their schedules/ticket sales set and I'm sure wanted a stand alone weekend to start their season. Would be nice for next year though.
http://www.racer.com/indycar/item/11...l-cancellation