I have had nobody notice it, or at least nobody notice it and say anything to me.
A few days ago I decided to try paying at Starbucks with my card on the watch and that's the first time someone noticed. The guy gasped and said "My first Apple Watch!" and called over another employee to watch as I paid with it. He noticed my tattoo on the side of my wrist and asked if it interfered with the watch at all. I told him that it is only an issue if it's under the sensor. He seemed pretty impressed with it and it worked really easily.
A few days ago I decided to try paying at Starbucks with my card on the watch and that's the first time someone noticed. The guy gasped and said "My first Apple Watch!" and called over another employee to watch as I paid with it. He noticed my tattoo on the side of my wrist and asked if it interfered with the watch at all. I told him that it is only an issue if it's under the sensor. He seemed pretty impressed with it and it worked really easily.