On The Beach is a great record - one of his most under-rated, I think. Tonight's The Night is much darker in tone, much more low key. I loaned it to a friend once, and he hated it; just didn't get it at all.
Apparently, when Neil and his band recorded the album, they sat around and played the songs and jammed, getting more and more loaded on tequilla, until Neil felt they'd reached the required state of, erm, looseness, and then they turned down the lights, sat around in a circle facing each other, and then hit the 'record' button, as it were.
While we're on the subject of Neil Young anecdotes, he played a UK tour in the mid 70's in support of Tonight's The Night, which hadn't actually been released at that point. He and his band played the whole record straight through to an underwhelmed and unappreciative audience (in Newcastle, I think.) At the end of it, Neil announced that they were going to play some stuff "that you've heard before" to audible sighs of relief from the audience, before playing the whole album through again. What a class act.