Glad to see another grandmother does the ornament gifts each year. I started this with my children (2 boys) from birth on--some bought with their age/interests in mind, others handmade--and I always put the date (year) on them. It was my intention to stop once they got older, but they objected to that idea. They are now 39 and 41, and I'm doing ornaments for sons, daughters-in-law, and grandchildren. The ornaments were gifts from the Christmas fairy (like the tooth fairy) and appeared on their bedside tables on Christmas Eve morning. When the boys and their families are here for Christmas, I still place them there for them. When they aren't, I mail them on that day.
My grandchildren always get to a certain age when they wonder about this and ask why the Christmas fairy comes only to my house. Sometimes they have already checked with friends and learned she doesn't come to their houses or wondered why she doesn't come to their other grandmother's house. The fact that they have mentioned these "Christmas fairy" gifts to their little friends and others is a good indication that they've appreciated them.
When each son was getting married, I boxed up their ornaments and gave them to the bride at one of their bridal showers to use on their first Christmas tree after they married. These were a big hit with both brides, and with the guests. Often young mothers in attendance would say they were going to begin that tradition with their own children.