Most powerful

Lady Gaga has toppled chat show queen Oprah Winfrey as the world's most powerful star. Gaga heads the new Forbes list of top showbiz and sports celebrities.

It's the first time in four years that Oprah has been pushed into second place - even though her £193million annual earnings are three times her rival's. Forbes rates Gaga as more influential because of her 32 million Facebook fans and ten million Twitter followers.

Here's the full top ten:

1) Lady Gaga
2) Oprah Winfrey
3) Justin Bieber
4) U2
5) Elton John
6) Tiger Woods
7) Taylor Swift
8) Bon Jovi
9) Simon Cowell
10) Lebron James