I've been noticing a lot of yellow flash from these late applications of glyphosate, but there is yellowing from soybean cyst nematodes and actually some yellowing from potassium deficiencies. The K deficiency is not because of low K levels in the soil, but rather the plants inability to properly utilize it because of the droughty conditions. Don't use this as an excuse to apply a foliar fertilizer though because it will do you no good. Simply, if the plant is unable to use the available potassium now, adding more will not make it any better since it is not a deficiency, but rather a physiological inability to mobilize the potassium. Given the conditions, I would expect to see other deficiency symptoms as well.
I also looked at some corn ears to see how pollination went. For the most part I'm impressed with how well the ears are filled out. There is some noticeable gaps in the ears but given the conditions, not bad. The picture above is a typical ear that I found today.