I announced to Kevin by giving him a box of cinnamon rolls with a note on it that said, "If I'm going to get fat, so are you!" The best part was that he didn't even notice the note. He just opened it up and started eating one. I had to tell him to read the package. :)
I also made a surprise (It was a surprise to me too!) announcement at the Thankful 13 half. The race has you submit a list of "thankfuls" and they print some of them up and display them along the course. They chose mine that said, "The baby in my tummy....Surprise!" and displayed it around mile 11. It was so fun to see it. This picture was taken after the race, when we went back to get the sign.