New potential cars for 2005.
GTS -
Aston Martin
Lambourghini
Maserati
Corvette C6R?
GT
Panoz
Nissan 350Z? Will the FIA GT car be ACO legal as well?
Then there is the Mazda suggestion, though which class is not a full certainly, though suggestions are LMP2 (If the class still exists
)
Porsche doesn't seem likely until 06', IF.
Audi could appear with a new "R9", IF other manufacturers commit. Big "IF" though.
Champion's participation in LMP class in 05' is dependent on having real competition in the ALMS LMP class in 05'. They are on record as stating they'll switch to a GTS Lambo if there is no LMP comp.