Bring cream cheese, sour cream, butter, and eggs to room temperature. In a large bowl blend together all ingredients except the eggs. Beat the eggs into the mixture one at a time, mixing well after each addition.
Pour mixture into a well-buttered 10-inch spring-form pan. Place into a large roasting pan that has been half filled with hot water.
Bake in a preheated 375 degrees F oven for approximately 1 hour. Remove from oven and let cool for 1 hour before removing sides of pan. Refrigerate.