I don't know, I think it could deffinatly be a sign. Especially sine it wasn't playful.
But I've also had one of my guy friends do that to me, telling me my hair was soft and it smelt good, but in front of his girlfriend. It really depends on the guy.
Lol I have a question similar to this!
they all have said that basically yes, he's into you, either that or he wants to be a hair stylist, but if you know he doesn't then it's definitely number unooo ;D