My wife and I just flew from JFK to NRT on 2/24. Had coach seats but used my VIPOW's to get upgraded. The Business section was almost all full - only 2 seats left on this Monday travel - and both seats were in the center middle section. Not a good upgrade seat (better than coach though).
Lately, I've seen the JFK-NRT route pretty packed in Bus, but better in 1st.