When federation is done 'right' you don't even notice it. Email for instance.
In my opinion social networks being in silos is as silly as something like email being in a silo. Really what we need is user buy in and that probably means figuring out how to interoperate with the various social networks like facebook and twitter.
It would be cool if the big social networks started thinking about breaking out of their silos and instead trying to be the gmail of federated social networks.