I know I did some maths and even the #1 boys name is usually only given to 2% of boys... I think once you get to #30ish it drops to something like 0.5%. So realistically even the most popular names aren't super popular, you just never know!
I have a Theodore. He is mostly called Theo but he knows his name is Theodore. I think it's adorable. I have met other Theos but not Theodore! He is a very sensitive boy who loves his mummy and is five going on 35!