Definition of mindshares:
(n) :
(often, most especially) A consumer's awareness of a particular brand or product compared to that of its rivals.
(n) :
The share (portion) of one's mind or headspace that has been garnered by a concept; the amount of attention or awareness that a concept gets in one's mind, especially in competition with the many other potential objects of attention, given the limits and opportunity cost of one's attention.