I got half way through this thread and had to add my bit.
inamuckingfuddle - I totally agree with you. I think there's nothing worse than seeing teenies with nail varnish, earrings and the like.
Dressing up is totally different and I agree that nail varnish and makeup in this context is fine, but I think it should be made clear to the child that it is dressing up, not for everyday, and a time set for its removal.
Perhaps it's my childhood that makes me feel this way - these are the values of my parents and my maternal Grandma, but I do not think they are old fashioned in the least. I think that children are growing up faster than my friends and I did - I'm 30 (what do you other 30's girls think?). I commute into London from SE London and, call me a snob, but I don't want my daughters (ok so only 22 weeks with No 1 bump of undetirmined sex!) going to school with hair full of gel and spray and faces plastered with make-up at the age of 13 (and younger), like the girls I see every morning. Perhaps they were the 4yrolds who wouldn't go out without their faces on.
On the whole Grandad thing, I think that is totally down to the Grandad in question. In he case of my FIL, it would never happen (he didn't stop talking about what he wanted to talk about as we delivered the pregnancy news - first grandchild btw - and thereafter made no comment), but it would be different with someone else. For instance my Dad's best friends. They're both about 60 and Grandads to girls and I wouldn't have any objections there.
This is all about personal opinions / attitude, the context, and the people involved. Everyone is entitled to their opinion. Don't berate inamuckingfuddle just because she has a different opinion and attitude to you!