Well a title of R&C quality, with a dev cycle of ~2 years would atleast want 500 to not be failure. 1 million would be good.
A sports title which gets recycled everyyear, with a 9 month dev cycle needs 200k to not be a failure.
edit: sports titles have licensing fees, but still you if your team was much bigger than 30, margins would be tight.
Ratchet hasn't been out for long, so It should hit 500k, eventually, but I would have thought it should be there already...
~S