1) Nursing makes you ravenous all the time. If its slower than me, I'll eat it. Good thing my big kids are fast movers. :)
2) The "baby" you left at home will be HUGE when you get back home with the new baby. I swear Carter grew 4 inches and gained 20 pounds while I was in the hospital. He's so big now!
3) Hormones and your big kids will make you cry for no good reason. Carter had a major melt-down on Monday (he was frustrated with a computer game, and over-tired and probably not knowing how to cope with being a little mad at me for being gone for 3 days and confused by his new role of big brother and "not the baby anymore") that had both me and him reduced to a puddle of tears. I spent the rest of the afternoon trying not to cry while I read books like "The Little Dump Truck" and "Monster Trucks"... books that would not make a sane person cry. Ever.
4) Dozing with a newborn snuggled onto you chest falls pretty darned high on the "best thing ever" list.
5) Having a baby makes everything take longer than it should. And you have less time to manage it all because, inevitably, the second your 2/3rds through your errands, its time to eat.
Oh... and the one I forgot earlier...
6) the Boppy really is the best baby product ever. Makes for easier nursing, easier sibling baby-holding, easy place to safely put baby for a snooze... I forgot how much I love my Boppy and how much MORE useful I found it with a 2nd (and how 3rd!) baby.