Jesus, forum's a bit heartless today isn't it? Leona Lewis, out of all of the trash that's come out of 'that market', is one of the prime examples of why it can be a good thing. She's globally well known and has never hurt a fly, nor bitched or moaned or become a diva. She's just done what she likes doing (that's singing, btw) to the best of her ability and made something for herself by it.
Why shouldn't she write about it? You don't have to have led a full life to write an autobiography, she's someone that wasn't born with fame but worked for it and came out top against thousands of others and took her name internationally and is well established within the music industry. There can't be many similar stories out there?
So with all this taken into account, her being punched in the face is completely out of order, and not really all that funny. There are many other people who throw their books at the public (Jordan, Jeremy Kyle) who are far more deserving of such a reward.