I do not see it in the documentation, but you can pass a function to the source parameter like this:
var source = [{'value': 1, 'text': 'fine'}, {'value': 2, 'text': 'bad'}];
$('#my_select').editable({
'mode' : 'inline',
'source': function() {
return source;
},
});
This way it always uses the updated source array. I updated your fiddle: http://jsfiddle.net/XN7np/4/