You can watch whether the trades go thru at the bid or ask to see if it was a limit sell or a limit buy being soaked up by a new buy order or new sell order respectively.
If you can't watch in real time then a rising VXN/VIX is a clue that new options buyers are busy and falling VXN/VIX is a clue new sellers are busy. But you have to be careful because calls influence the VXN/VIX values.
I suspect the equity P/C is higher than might be expected at a major top because put sellers are complacent. This is a bearish sign.
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