I can't see 
on-board vocal harmony being a big deal for this one...most people are using 
outboard processors.
If this instrument sounds as good as the BK-7M (and it should), it will have a much better sound than the TOTL G-70, in my opinion..I know DonM and a few others were very impressed with the BK-7M's styles and voices. They were sayin' E-80 quality.
A 76-note possibility?
Maybe, but I have my doubts...the idea is to keep the 
footprint of these 
backing instruments as small as possible...they aren't for piano players, but for the singer/keyboardist/guitarist looking for something to use on stage. Small is good in this situation.
This sure looks a far better deal than the Korg microArranger, even though it's price is a bit higher. It also looks far more 
professional.
 It will be interesting to see who switches over...I have a feeling a certain fella from New Jersey might make the move... 

  Ian