it also says this;
Why say "top motorsport championships" if it's exclusively for Indycar?
"The partnership between HPD and Magneti Marelli will see the two companies utilize their extensive research and development resources to assist the HPD effort in the IZOD IndyCar Series. Plans call for the two companies to extend the program to include other pinnacle racing series, such as the World Endurance Championship and North American road racing that will combine the American Le Mans Series with the Grand-Am Championship starting in 2014. "
Details on Honda's new F1 project isnt clear yet. Should be R&D in Japan such as Tochigi that will be in charge of F1 engine, not HPD. There will be technology sharing and transfer b/w US and Japan but I dont think we'll have clear picture on their operations.