We like it to be a surprise at birth however when we found out we were expecting Triplets we wanted to know the sex during the ultrasound. We ended up losing Baby C but we did find out A & B were boys and were thrilled because we already had 2 girls! :)
now that we have had both boys and girls we will always wait until birth to find out.
To answer your question - it was just as exciting to find out during the ultrasound as it was at the birth. We just didn't tell ANYONE what the twins were until they were born. :) We told everyone we were waiting to find out. LOL