[Chesterbelloc]

I didn't see anything that I didn't expect to see - it was a fireball with a plume trailing behind it. No sudden changes in brightness - nothing separating off from it. I was going to video tape it, but didn't. It passed slightly north of me - I'm at Shaver Lake, California.

[winodog]

I noticed the change in brightness after it went by (probaly in UT or AZ by that time). It seemed to go dim for a split second, then brightened back up.
It would be something like the flash the fella in CA mentioned but more like the light was turned off for just a second.