As the mock up website shows:
More Sounds
More Instruments
Infinite Possibilities

This applies to the Pluggin as there is so much material being release.
I think there will be more complex recorded material with more chords so it's not substituting any.
The same instrument FX/DI used for substyles/patterns/solos so the one instrument is used on the one track playing differently in different sections keeping the same sound rather than just A section or B section option.
Integrating with something like Melodyne (alternative) down the track.

All of this in a studio environment will give so much creative control with 24bit 48k audio, all RealDrum Stems, all time signatures.
It would have to become an industry standard goto for any studio.

Guys, you need to look way beyond Band In A Box, a fun thing for learning and practicing.
Look at it as any world class session musician at you finger tips, in any DAW and any studio.