I'm only 7 weeks old now but I'm already sleeping through the night most nights! Last night I went to bed at 11 PM and woke up at 5:45 AM. Even then I wasn't fussing, but Daddy checked on me, saw that I was awake, and decided they might as well feed me before I started getting cranky.
I definitely think I've got Mommy's "sleep gene"! We love to sleep!