I don't understand why Flash RAM (FRAM) is so popular, (apparently over Battery-Backed Ram [BBR]).

My looking into this, (which has been enormously difficult, since it is apparently presumed that everyone already knows everything about this stuff; for instance it took me forever to find out if FRAM maintained its data when power was removed), has lead me to understand that there is a much more limited read/write life for FRAM than for BBR, right?

It also seems that BBR would make In-System Programming easier.

Anyway, thoughts?