Photomanipulation is used all the time in CD's, book covers, movie posters etc. and shows a more commercial side to the art of composite imagery. I've started looking into album art and cover art as I find it to be a great possibility of work I can try and get after CIT. I love that although it is commercial work, the photographer often has a great role to play in the design and creativity put into it.
Here are just a few examples of album art that uses photomanipulation: