In the footage, Raiden (looking a bit upgraded since his appearance in Metal Gear Solid 4) does combat with a robotic adversary (seen above). After slicing it apart, Raiden rips out its cybernetic spine and absorbs its energy, seemingly powering himself up.
Later, gameplay footage revealed the ability to cut anything in the environment: enemy soldiers, girders, cars, bricks. Furthermore, Raiden is able to launch enemy soldiers into mid-air triggering a slow-motion effect, which can be used to carefully slice off legs, heads, arms, what have you.
Metal Gear Solid: Rising is in development for the Xbox 360, PlayStation 3, and PC. No release date is given.