frigg is good at guessing such* by the shape of a momma's tummy, so I took a pic for her and thought I'd open it up to a poll to see if anyone else shares her prowess.
Don't make fun of a pregnant lady in spandex! :P
From the looks of you, I say:
* We met up in Paris while I was pregnant with Sprout, and she did say "a girl," but she didn't want to declare herself 100% because she didn't think I was showing enough at that time. :P