On the way up, people would talk about AAPL as its own asset class because of how well it used to trade relative to the S&P 500. Now on the way down, AAPL has remained relatively uncorrelated to the index, but not in a way that most people want to see. Apple is now down almost 30% from its peak levels hit in September of last year. Such a steep fall would certainly be considered a crash for any other asset class.
In fact, AAPL's recent decline has paced the 2008 September-March crash quite well. If AAPL were to continue to pace the decline it would bottom somewhere around $350.