  We speculate that the dark halos of dwarf galaxies and low surface brightness
galaxies soften their central cusps by the decay of a fraction of cold dark
matter (CDM) particles to a stable particle with a recoiling velocity of a few
tens km s$^{-1}$, after they have driven the formation of galactic halos. This
process, however, does not necessarily produce a significant reduction of the
central dark matter density of satellite dwarf spheroidals like Draco or
Fornax. It is shown that the recovered distribution of concentration parameters
$c$ for the initial (before decay) Navarro-Frenk-White halos, is in good
agreement with CDM predictions. Other interesting potentials of unstable CDM
are highlighted.
