From watching the video, I think the Raven Turn is like a B&M Immelman. Instead of the track doing a half barrel roll (which turns the riders back to the upright position) after the half loop, the 4D will rotate the seats 180 degrees. Also, the riders will be traveling backwards after the turn. (assuming they went into it foreward)
Sound confusing? Just wait until this thing gets built, then the real confusion will begin. (what counts as an inversion, how many inversions are there)
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"X" marks the spot in 2001!