Facebook could probably go in either camp. I'm sure they write some of their business logic in php, but they made Thrift for a reason. In particular, isn't th

Facebook could probably go in either camp. I'm sure they write some of their business logic in php, but they made Thrift for a reason. In particular, isn't their chat written in Erlang and feed stuff written in c++? I've read that they even use Java for some things.