I found the book absolutely hilarious. In an earlier comment about
Lucky Jim, I referred to a certain "cruelty" which made me uneasy. I was thinking of the portrayal of Margaret. I thought it cruel that someone so emotionally fragile that she would attempt suicide could be presented in a comic manner. However, I put that feeling in storage as I read and, sure enough, Amis had a superb twist on that situation. It turns out that Margaret was an emotional vampire who had no intention of actually taking her own life--she only used the threat to create in others a particularly nasty guilt feeling. She would then employ this to control their feelings towards her.
Bfisher commented on the humour as having an equivalence with the physical comedy we see in slapstick films. I think that insight is one of the core aspects of the book. An example that had me laughing out loud was the point where Walsh has a losing battle with a revolving door!
I too loved that ending!
Lucky Jim is one of the most enjoyable reading experience I have had for some time.