If it was just a one-time deal, I would have let it go. Crestliner said "The same jerk that likes to make noise all day on sundays running a back hoe/bobcat" - which says to me, the neighbor has quite a project going on! And works, so has a limited time to work on it. I'd be forgiving of a neighbor who was so wrapped up in a project that they wanted to finish, even if it was after 9 pm. Now, if it was every single night, or went on past 11 or so, that would be different.
I think crestliner would be happier on lots of land, with few people nearby. But based on past posts, he'd probably take the birds singing as a personal assault!