[jacquesm]

The real life equivalent of this for me is Christmas cards.

I never send them, but I receive piles of them every year. It's really not nice of me but I stuff them in the paper bin unless they're from close family or home made and not printed.

When it's mid summer though I tend to drop in on people just to say hi and ask how they're doing, I prefer to do that than to send a Christmas card just because 'it's the social thing to do', I don't feel as though I'm obliged to return the favor and the facebook 'demands of reciprocity' I can do without just as well.