Quote from MKTrader:
If you're a swing or position trader, just avoid all the permabull/permabear arguments and focus on the only two important data points today:
1) Where the S&P 500 closes (above/below 1000)
2) Where the Nasdaq closes (above/below 2000)
Major psych levels (triple 000) being tested for two indices--this doesn't happen very often.
Of the two, the Nasdaq is more important, since it tends to lead both rallies and corrections. Both will probably toy with these levels a bit longer, but there has to be a strong up/down break soon. Weekly closes are pretty significant...