On the weekly chart, note that 2 layers of support were already taken out at around 2135 and 2110 (former chart highs).
The new support levels are round numbers (currently battling for 2100) and the 40wk line.
I also think its interesting that the support breaks (best seen on the the past 2 days) have come in fairly light .
Like everything with trend following, we'll have to wait and see what happens. Caution is warranted for sure but its worth keeping in mind that every time the market has seemed like it was ready to roll over and die, it has miraculously rebounded. As they say... it ain't over till its over!