toyota trd and rod millen (stillen) did a 500hp new celica at toyotas request, using the 3s-gte.
from what i've seen the supra will probably look like the one with the big bonnet (the silver one a few posts down) the supercar thing isn't for the supra, it was tipped to be an AWD v10 (to make use of the F1 investment) twin turbo car seperate to the supra, and i hope they make them both!
3rd, i've never seen a scion, i think they might be a U.S. special, and i can't see the celica being stopped in japan cause they sell quite a few over this way. The Scion would never take off here, it would compete against the sportivo corolla if anything!