also forgot to mention two random things:
1. don't discount her adjusting to baby. It will take a loooong time to get adjusted to a sibling. They may not even end up friends (I know *gasp* every parent's nightmare but read Siblings Without Rivalry to understand what I mean and get great tools for parenting siblings).
She will go through an adjustment period now and then again when her little sis becomes mobile right before the first year and starts to get into her stuff/zone/toys. Prepare for it as separation, time spent alone with a parent and proactive parenting will be your friends during this time.
Also it's okay to let her fall in love with daddy at this stage. Right around when I had #2 is when my husband became the guy that hung the moon for my oldest. He still loves me and really likes spending time with me now but he also loves to see daddy come home and get to spend time with him on the weekends.
2. Don't do the "big girl thing". As in, "your too much of a big girl for X or you're too big for Y or you can't do blah, blah because you're a big girl". Seriously, if she wants to regress in certain areas and play baby, do not resist it. It's totally normal for older siblings to test the waters of being a baby or acting younger to see if you still love them. The less you resist that bit the more quickly she'll move through it.