WHAT. A. SHOW.
I was so worried they were going to call the show when the lightning kept getting closer and closer. I couldn't tell how much of the lightning those down front could actually see, but there was a LOT of it - a lot of cloud-to-cloud flashes, but also a good number of big ol' cloud-to-ground strikes, and at each one, my section all went "OOOOOOH!"
Seriously, though - I kept looking to see if anyone was going to run on the stage and tell Edge or Bono to pull the plug.
As far as I could tell, the place was hopping - I think the only people sitting in my section were my parents (their feet hurt! but they only sat for about a half hour), and a couple in front of me who huddled under a half-raised umbrella.
Everyone around us was completely into it, and people either pulled out their ponchos like troopers, or sat and clutched their drowned-rat selves and kept grinning. One guy left early right after the closest lightning strike. He looked up at the sky right after the flash, and I could see it on his face: "Welp, that's enough of that." And he left.
My parents enjoyed the show, my step-sister LOVED it. Between the rain, the lighting and the fireworks over the river, it was quite a show!
Oh yeah, and U2 put on a hell of a show, too.
Torrential rain makes even a standard setlist into a great show.