What's the difference between io.sockets.emit and socket.broadcast.emit? Is it only that broadcast emits to everyone BUT the socket that sends it?
It seems like they can be used interchangeably:
io.sockets.on('connection', function (socket) {
  //these should do the same thing  
  io.sockets.emit('this', { receivers: 'everyone'});
  socket.broadcast.emit('this', { receivers: 'everyone but socket'}); //emits to everyone but socket
  socket.emit('this', { receivers: 'socket'}); //emits to socket
});
 
				
				io.sockets.emit will send to all the clients
socket.broadcast.emit will send the message to all the other clients  except the newly created connection
This Socket.IO Wiki post will help everyone reading this question:
socket.broadcast.emit() behaves similar to io.sockets.emit, but instead
of emitting to all connected sockets it will emit to all connected
socket except the one it is being called on. So in this case the socket
referenced by socket will not receive  the event.