Mine was 220º, with ambient air at about 95º, at about 70 mph.
Over the weekend, with ambient air in the low 80s, it was about 210º at ~45 mph. Now that I have a ScanGauge, I know the water temp was ~200º.
I'm off to Colorado on Wednesday and will have a little more highway data after I return.
Oil: Meijer 10W40 Synth. (based on the packaging, I will postulate that it's made by Mobil)