The jet will run the Tokyo-Miyazaki/Tokyo-Kagoshima route for four years, starting December 1st.
The “RetroJet” fad is something new among airlines since about 2000. A small number of jets in the fleet will be repainted with the some historic livery. Here are some good examples (click to enlarge):
In Europe, these are usually state owned airlines (deregulation is fairly recent so none of the private lines have any ‘retro’ to retro to), but in the US you do see some (like US Airways using the old PSA livery). Is it a terrible waste of money? Commercial planes need to be repainted every few years, so that is not an additional expense – although you would need to pay a design or branding firm (such as Landor & Associates or Newell/Sorrell Interbrand) to come up with the new livery.
I generally like retro jets, but I think the ‘Mohican Blue’ is not a great improvement over their current ‘Triton Blue’ livery.