Yesterday the S&P 500 closed below 2,350. This level was support since the beginning of April. It was broken in March as well, but it rebounded quickly after becoming oversold. Now we may not see a snap back like we did then because the market is not currently oversold. If it does head lower there will probably be support around the 2,300 level because it as resistance in January as well as being a nice round number...which markets love these days due to the ETF mania that is occurring.
The key to seeing if a large selloff down to the 2,300 level occurs has a lot to do with whether the XLFs hold support at the $23 level. If this level beaks the broader markets will make a meaningful move lower.