longer.js

/*
 * Long and Dreary.
 */
var json = xml2json.parser(response_text),
    query_result = json.envelope.body.queryresponse.result,
    users = [];

// Build up a list of {{sd.User}}s to return to the view.
if(query_result.size == 1){

    // Only a single user returned from the search
    users.push(new sd.User(query_result.records));
} else if(query_result.size > 0){
    for (var query_i=0; query_i < query_result.records.length; query_i++) {
      users.push(new sd.User(query_result.records[query_i]));
    };
}
return users

shorter.js

/*
 * Short and Sweet.
 */
var json = xml2json.parser(response_text),
    query_result = json.envelope.body.queryresponse.result,
    records = query_result.records.length ? query_result.records : [query_result.records],
    users = [];
        
// Build up a list of {{sd.User}}s to return to the view.
for (record in records) {
    users.push(new sd.User(record));
};

return users;

The ternary operator works here, since it's a straight object or a collection of objects in my case. It wouldn't work, however if it was only a string. (I do have cases of that [a collection of strings or a single string]) in my project right now, but I think ternary is the way to go in this case. Thx!

Also, I can't incorporate the for ( x in y ) iterator, because I've locked myself into an Array prototype extension, and it would Iterate over that function after the indexes of the array.