In this server side code:
socket.emit('news', { hello: data});
...you're sending the array as the hello
property of an object, but this client-side code:
document.write(data[i].hello.name);
...is expecting the top-level to be an array, with individual hello
properties for each entry. Change that to:
document.write(data.hello[i].name);
...so you're indexing into the array.
It would probably be best, as well, to limit your loop using the array's length
rather than a hardcoded value:
for(var i=0;i<data.hello.length;i++){