I think I'm going to start wearing the definition of sincerity pinned to my shirt, written in capital letters. Honestly, have we become so jaded that any statement of thanks or praise is seen as stupid, creepy, or false? I certainly hope not.
velocity:
I've noticed that as well, even in myself. It took me a while to adjust to my boyfriend's sincerity when we first started talking. I'd just figured he was saying nice things because he had an agenda.