Although the book was written a long time ago, I found it quite pertinent reading it coming up to Christmas. I get a little bah humbug at Christmas time myself. Not like Scrooge - I do celebrate Christmas. However, I get so involved in the preparations: presents, Christmas turkey, cleaning the house for guests etc.. that I can get stressed and negative.
To me the book is very "fellowship of man and woman", about spreading love rather than, well I guess an absence of love - or indifference. I don't think Scrooge really hated anyone, he was just completely selfish.
I think I understand selfishness because I believe we live in a very selfish world. I see it as a form of protection - a shield against the barrage of negative and hateful people, institutions and conditions humanity faces.
To me, A Christmas Carol encourages us to embrace each other with the spirit of goodwill as much as possible - even if only during Christmas time. And as much as I think selfishness equals protection - at the same time I think optimistic goodwill to others is restorative.
Anyway - I guess I took a personal message from the book rather than anything else. I didn't read the annotated version and consumed the story without much understanding of what was occurring in Dickens' England at the time of writing.