Is the bull market which started from the 2002 low at 768 in the S&P and 7200 in the Dow over? I don't think so. In my experience the market does not announce a long term top with a spectacular 10 day drop from its all-time high.
Instead I think it more likely that we shall see new all-time highs later this year and that the nearly 100 point drop in the S&P and 700 point drop in the Dow has brought the market close to an important low. I think that at yesterday's intraday low at 1465 in the cash S&P and 13330 in the Dow the averages were at worst only 1-3% from the ultimate low of this reaction.
One reason that encourages me in this view is that the drop has been accompanied by widely known, bad news on the front pages of many newspapers. In my experience the start of a bear market is accompanied by good news about the economy. Only towards the middle and end of the bear market does the bad news occupy the front pages and magazine covers.
To illustrate my point take a look above this post at the front pages of The New York Times which appeared this morning and this past Wednesday. Both front pages featured bearish stories about the sub-prime lending problems and the associated "flight from risk". I have always made money fading the Times and I don't think this will be an exception to the rule.