This is pedantic. So, since GT4 is coming to the PSP in a few months, we cannot call GT an exclusive, I guess? We can safely assume GT5 will come to the PSP or PSP2 eventually, after all.
God of War also came to the PSP, although it's not identical, it's close enough (e.g. as we can say Mario came to the DS). To take your phrase, "I can play God of War without a PS2 or PS3."
Another of your examples, Viva Pinata, also came to the PC and DS.
As for Dead or Alive, DOA Code Cronus was in the works before Itagaki left the building. No idea what its current status is.
Bottom line, this is the console forum. It's implicit that we're talking about console exclusivity. Leave the PC and handhelds out of it.