The article mentions this (i.e. that an open standard should be created for IMs between different social networks). I would say that in most cases this doesn't

The article mentions this (i.e. that an open standard should be created for IMs between different social networks). I would say that in most cases this doesn't even matter, everyone in my social network, and nearly every new person I meet, is on Facebook, I admit there's obviously a bias there i.e. the demographic of Facebook members probably matches that of my 'real-life' social network.