I hate the Facebook, try as I might I've had zero success in migrating my family and friends to superior services like twitter & google+. (I'm gen x btw). Reason being is my non computer literate family and friends can't cope with the cognitive dissonance of learning yet another www site on the internet. If they do manage to do so, then there's no-one there, except boring self-promoters (hello twitter!). So Facebook will be around for a long time to come and people like me who know there's better alternatives will still be forced to use it.
Getting back on topic, postponing the IPO makes a tonne of sense. The markets are in turmoil with Greece and Italy about to default. For an IPO of the size of Facebook, any sensible banker would wait and see.
Plus the USA has its election next year, so inevitably the pork barrel will come out. No doubt that will add a couple of digits to the user/revenue/ebitda mulitple that Facebook will be valued at.