[evilduck]

Maybe. But on the other hand, they've provided me their service for free for several years now and putting it behind a pay-wall would effectively be holding my social network hostage.

Not only do I value Facebook's service at less than $1/mo, but I'd be highly resentful of the switch, especially if I percieved it as a money grab or network lock-in attempt, instead of a reflection of their increasing costs (which could still be problematic if I knew they were wasting lots of money).