Just finished a bottle of blue stuff. Not sure exactly what it was...sort of schnapps like. Blue synthetic raspberry flavoured, sugary EtOH solution. Thats about as close as I can get to describing it. Was ok, nothing special. Just cheap, passable 15% ethanol thats blue flavoured. And yes, it appears that 'blue' is actually a flavour, going from the number of drinks available going by that description, such as for instance WKD vodka blue. In that case there appears also to be a 'red' flavour.
Surely it must be a spesh thing to wonder 'hmm...does anybody involved in their marketing and/or design dept. have synaesthesia