Brands don't normally compliment their competitors because they don't want to give their competitor free publicity, but what happened with Xbox and PlayStation generated a different result when they congratulated each other on Twitter.

Apparently, compliments generate over ten times more likes and retweets for the brands than their usual content.

The study showed that brand-to-brand praise makes the viewers view the brand as "warmer" -- meaning that they're being perceived as more friendly and trustworthy, after complimenting a competitor.

It is this warmth that drives favorable outcomes for the pra...