Detroit, be afraid, be very afraid, writes deputy editor Graeme Roberts. The V8-powered full-size Nissan Titan pickup truck has only just gone on sale in the US to give a Japanese transplant maker its first attack on a market segment that Detroit's Big Three once thought was their sacred preserve, and already Honda has waded in with the SUT Concept, unveiling at the Detroit show a smaller V6-powered pickup truck concept it will launch into production next year.