gistfile1.txt

var responseJson = [
	{type: 'input', id: 'key1', styles:{display:'block', color: 'red'}, someprop:'abc', someotherprop:'bcd'},
	{type: 'radio', id: 'key2', styles:{display:'inline', color: 'blue'}, someprop:'xyz', someotherprop:'z'}
]

var parseResponse = function(response) {
    var result = [];
    for (var i=0; i<response.length; i++) {
        var resultObj = {
        	type: response[i].type,
        	id: response[i].id,
        	styles: response[i].styles,
        	someprop: response[i].someprop
        }
        result.push(resultObj);
    }
    return result;
}

var parseResponse2 = function(response) {
    return _.map(response, function(item){
    	return _.pick(item, 'type', 'id', 'styles', 'someprop');
	});
}

var result = parseResponse(responseJson);
var result = parseResponse2(responseJson);