I CAN'T CHOOSE! They both have their good and bad.
Television: British comedy is the best, with my exception being Curb Your Enthusiasm (American), which is my favourite television show of all time. (Alongside The Sopranos and Freaks and Geeks.)
Books: This is way too hard as my book collection contains a diverse mix of works from a range of nationalities. But my favourite is Oscar Wilde, so there you go.
Music: I can't choose! I'd probably say 55% American, with the remainder being from the U.K. (I'm currently listening to The Raincoats, who are from Scotland.) However, a lot of my favourite bands ever are from other countries - Refused (Sweden), Cult of Luna (Sweden), The Clean (New Zealand), Envy (Japan)...etc.
Oh, and one of my favourite films is Taxi Driver which is........American.
I'd prefer to live in the U.K though, although I do love certain parts of the States too.
But since Britain gave us Morrissey I'm gravitating more towards them.