How soon are you announcing pregnancy?

Mary
Hey mamas-to-be!
Surprise surprise, my hubby & I are STOKED to tell our loved ones about our little bean. We told my folks, in laws, best friends, and grandparents over the past few weeks. I'm 8 weeks along, going in for the first ultrasound tomorrow!
Originally we decided on end of the first trimester as the timeline for the public announcement, and week 10 telling the rest of the family/people who should hear it from us versus Facebook. But my sis-in-law said she was waiting until her second ultrasound with the gender to announce her second babe, and another close first who's expecting her first announced hers around week 10. 
What are your thoughts of pros/cons of waiting longer, telling early, or sticking with the norm at the end of tri one?? xoxoxo