original.js

function load(fixtures, onComplete) {
    async.parallel(fixtures.map(function(fixture) {
        return function(cb) {
            store(fixture, function(err, result) {
                cb(err, result);
            });
        };
    }), onComplete);
}

describe("moods tests", function() {
    var moods = [
        "2013-02-01:n1k0:sunny"
      , "2013-02-02:n1k0:cloudy"
      , "2013-02-03:n1k0:stormy"
      , "2013-02-04:n1k0:rainy"
      // … we could add many more
    ];

    it ("should do something useful with moods", function(done) {
        load(moods, function(err, storedMoods) {
            done(err || undefined); // to make a fair comparison
        });
    });
});

withPromise.js

function load(fixtures) {
    return Q.all(fixtures.map(store));
}

describe("moods tests", function() {
    var moods = [
        "2013-02-01:n1k0:sunny"
      , "2013-02-02:n1k0:cloudy"
      , "2013-02-03:n1k0:stormy"
      , "2013-02-04:n1k0:rainy"
      // … we could add many more
    ];
    // a promise-freindly test framework would expect promises to be returned
    it ("should do something useful with moods", function() {
        return load(moods);
    });
});