Congratulations peppercold! I'm 18 weeks and also expecting DS3! I'm actually thrilled to be having another boy (I would have been thrilled either way - just happy that they're healthy and there), but prepare yourself for some insensitive/ignorant reactions/comments. I'm amazed by the amount of people who think I must be having a third because I wanted a girl - and some can't hide this look of horror that passes over their face when I tell them.
Enjoy all those little boy cuddles when they come!