A couple of weeks ago (9/12 to be exact) VXST was a tad lower than VIX despite a pretty tough week for the S&P 500. It appeared that VXST relative to VIX indicated a lack of fear and I talked about how the market has been lulled into complacency due to the S&P 500 continuously rebounding from any weakness. That happened again this week and VXST reacted by putting up a 10 handle before the week was over.
The VXST curve returned to normal after being a little inverted last week. Forgive the Monday morning quarterback in me, but the inversion could be taken as an indication that the S&P 500 was going to run to new highs.
Finally, Vance Harwood has some interest analysis of VXST futures versus VIX in a column that showed the price action of VXST futures relative to VIX along with some analysis of other volatility related instruments –