Today's sharp decline makes it easier to construct an motive wave count - see the red count in the cash and futures charts below. The most likely candidate for the motive wave is wave C-down of and expanded flat since the April high, and to a lesser degree either a P-down scenario or a part of a complex multi-year (x) wave discussed in Let's Recount II (long term) (11/12/10) as "[IV]-small-flat".
It is still relatively complicated to discern the structure of a corrective wave count. However, we may just have enough waves to make a decent attempt. The structure is likely a zigzag-x-flat in futures - see the black count. The form looks better with an additional lower low tomorrow, perhaps to get the market close to the 0.382 retrace. But a lower low may or may not be required. The most likely candidate for the corrective wave is minor wave 4 since the late August low.