Yes I agree - unless you have a very sophisticated 8 year old! But the language isn't a problem, and I personally thought it a very funny film. We saw it over the Christmas holidays and it was packed - mainly families I think.
I liked the original movies too and when I heard about this film I was hoping that they would keep it set in the same time rather than trying to update it. However, I quickly changed my mind. Basically it is the same jokes as the original films but with a modern twist. There are some very obvious references to other movies but I saw that as more of a joke than deliberate attempts to copy as suggested by a previous poster.
My daughter (12) is going to see it again with her friend's family at the weekend - friend's mother is a bit more straight laced than me I think so it will be interesting to see what she makes of it!