A.M.
I would suggest also reading the book from Sleepy Planet. Jill Spivack is great and really knows how to make you feel confident with your decision. If you leave in the LA area you can even meet with her in person.
You should also consider getting a video monitor in the room (Summer makes a great one) so that you can see him while he is in the crib and you will feel confident that he is okay even though he might be crying.
The best advice - get him in the crib - you will have such a better night sleep and so will he!! It might be tough at first but it is worth it!