Quote from Hello_Dollars:
While that's correct, the new VIX, which has been pointed out is calculated differently and is based on the SPX rather than the OEX, actually correlates pretty well with the old VIX (though it does skew slightly lower). Given that correlation, it should continue to work as a contrary sentiment indicator (that is, to the extent the VIX still "works" for such purposes, which is in some doubt). Still, I keep both the new VIX and the VXO on my screen. For more detail, the CBOE has a whitepaper and maintains historical data for both the new and old VIX on its website.