It'll be decades before quantum computers become mainstream. We might see hybrids or maybe even graphics cards with both a physix and quantum chip on them and initially it'll only be used for bettering security and later on for modelling things, but otherwise regular CPUs will continue to dominate and things won't change much.
Programming for quantumn chips will be about as niche as programming a PIC microchip is today, only a small number of developers will be doing it and they will specialise in doing just that.