If you want to know whether an idea is good or bad for business, just look at where the market forces are taking the industry leaders.

Hallmark has decided that celebrating all civil marriages is a good business decision and launched a concomitant line of greeting cards.

They think they can make money off of them, which means that Hallmark stands to lose revenue if Proposition 8 passes.

Prop 8 is bad for Hallmark, and bad for business.