I think Nathan Drake is, because his games are better and the characters are better developed and the story is amazing. Kratos is awesome, but his games just aren't as good as the uncharted series. So I think Nathan Drake is the face of Playstation.
This is where I say that you are wrong! The Uncharted series has only been on the PS3. God of War started on the PS2 and pushed the hardware for the system. God of War is on the PSP, God of War isn't over yet. I see them making another and having one on the PSVita.
Kratos wins this face off. Uncharted reminds me of Tombraider but with a guy instead of Lara Croft. God of War is well God of War, nothing really compares to it!
Uncharted is a good series but can't compare to God of War, sorry!