Full disclosure: I don't have two kids. Yet. I will say the last time I won a prize from Cool Mom Pics, I was mom to an eight-month-old and wondering what I was going to do with a pair of Psi Band that I was absolutely delighted to win. I found out a few weeks later, I was a pregnant mom to a nine-month-old, and quite nauseous so the Psi Band came in pretty hand. So if I find out I'm having twins in two weeks, I know who to blame.
Anyway, in addition to taking care of my 10-month-old, I also take care of another baby, roughly the same age four days a week. While not nearly the same as birthing and/or raising two, I do a have a little experience taking care of two at once.
It's going to be hard. The first couple of weeks Danny was here were tough. The boys were getting to know each other, I was getting to know them, Danny was getting to know me. Two is twice as much work, no doubt about it.
Then it got better. They started napping at the same time (most days), playing well together (most days), and I'm actually able to keep my household above water (most days.) And on the days it doesn't all come together, I've learned to just let it go.
So, my advice: Don't be afraid to just let something go; be it the laundry or the dishes (house work in general), dinner (order take out), calling your mother or best friend, updating your blog, letting your spouse give the kid a bottle so you can sleep for more than 2 consecutive hours even if you really want to exclusively breastfeed. Just give yourself a break - you don't have to be superwoman, you just have to be the best mom you can be.
Good luck, and I can't wait to read all your good advice, because I'll be needing it myself come December!