Update: here's a load more info, from the official site.
"The Hokkaido location is set within the grounds of the hyper-exclusive GAMA private hospital and resort. This secluded facility is a fusion of Japanese beauty and cutting-edge technology, featuring its own Zen gardens, organic sushi restaurant and traditional Japanese hot spring."
"Episode 6: Hokkaido features a mission called 'Situs Inversus' and is the culmination of everything players will have learnt in terms of both gameplay and story. As players have come to expect, the location will also be used for Escalation Contracts, Elusive Targets and community-created Featured Contracts. Plus, we'll have the usual array of weapon and gear unlocks that can be used across all previous locations."
Original story: Everyone's second-favourite bald assassin (after Mike from Breaking Bad) is heading to Hokkaido, Japan soon, what with Hitman's first season wrapping up in a few short weeks. As revealed by the following teaser trailer, Episode 6: Hokkaido will arrive on October 31, featuring katanas, a luxury hospital, and a big old mountain, which are not especially Halloween-y things.
We know from Hitman's Twitter page that Agent 47 has come to Hokkaido to "locate two targets at a hyper-exclusive private hospital", before presumably downgrading their conditions from 'alive' to 'dead'. Episode 6 will be the season finale of Hitman, and I'm sure we'll hear more about what's included soon.