No, 'Katy Hudson' doesn't count. Prism is Katy PERRY'S 3rd album. I once asked the question on the forum because I was confused about Katy's mentioning that Prism should not be referred to as her fourth album. Also other sorts of albums, such as 'greatest hits', live albums etc don't count in general as I was told at the time. Katy always objects to the '4th album' mention.