Although the iPhone OS 2.1 update is not yet available, the iPod touch update was available shortly after Steve Jobs left the stage at the Let’s Rock event. While the iPhone update will supposedly fix major problems like dropped calls and application crashes, the update for iPod touch does not have such clearly defined goals.

Investors clearly had high hopes for Apple’s “Let’s Rock” event. The stock, which began the day at $156.99, spiked nearly two dollars to $158.83 a few minutes before the event began. During the event, however, the stock shed nearly five dollars, to end at $153.24. After the event closed, the stock began a slow, upward trend, but still has yet to reach its starting price or peak volume. So, what were investors looking for that has them so disappointed?

Thoughts after the break.