The official name for this show in Japan is "Fullmetal Alchemist" which was renamed as "Fullmetal Alchemist: Brotherhood" in the English version. The reason for the renaming was to avoid confusing it with the first series which also shared the same title.
In the Episode 58, a character resembling Dante, the main villain from the first Fullmetal Alchemist anime series is seen in a cameo appearance.
Isaac is a new, original character, not present in the FMA manga or the previous animated productions. He was expressly created for this new anime, and he was designed by 'Hiromu Arawawa' herself (the original creator).
The English voice actors for Lust and Mustang, Laura Bailey and Travis Willingham, are married in real life.
Edward greatly dislikes milk, either for its taste, the fact that it is "an opaque, white liquid secreted by a cow" or both. He does, however, greatly enjoy stew and marvels that something comprised mainly of milk can taste so good. It is often joked about in both the manga and the anime the reason he is so short is because he refuses to drink milk. Incidentally, Hiromu Arakawa grew up on a dairy farm as a child.