A DNF for me today too. Completely my own fault for being improperly dressed for the conditions.
Once I'd got wet, I got cold pretty quickly. I tried stopping in Henley and getting a pair of washing up gloves to try and dry out and warm up my fingers, which worked for a while and improved things a bit. But boots full of dirty flood water weren't helping matters either. So when I spotted the sign on the way out of Watlington saying it was only 4 miles back to the start, that was game over, and there was no way I was convincing myself to carry on.
A massive chapeau to all those that carried on and made it round, your certainly made of stronger stuff than me.