During my trip in April Shaun asked me to check on the genetics of white lions (I am a geneticist). While making my Holiday cards from pictures from my favorite vacation of all time I remembered the request.
Here is a great website about white lions: http://www.animalpicturesarchive.com/view.php?tid=3&did=27297
and Shaun was correct they are not albinos but have a leucistic trait from a mutation (known as chinchilla) that inhibits the deposition of pigment along the hair shaft, restricting it to the tips. It is thought this trait has been lost in the wild but you never know!!
Happy Holidays and thank you again for the most enjoyable trip EVER.