I'm 20 weeks now with first, and for the last 4-5 weeks have been noticing boob leakage. Last night it was so bad I woke up with spots on the sheets and some nice crusty stuff across my nipples (helpfully pointed out by DH).
I didn't think this happened so early in pregnancy. I'm guessing it's probably normal, but just wasn't expecting it so soon. Noticing crusty bits on the inside of my bra too, blech. Don't want to be wearing pads just yet!
Hope it means breastfeeding will work out ok.