1. A method comprising: receiving content placement rules that describe conditions for placement of content elements within an interactive television (iTV) application at defined locations along multiple dimensions, wherein each content element of the content elements is identified by an attribute that references an associated definition of a programming campaign, said definition of the programming campaign including a key that uniquely identifies the programming campaign, a listing of candidate content elements, and a rule for selecting one content element from among the candidate content elements, wherein the content placement rules prioritize placement of each of the content elements at one of the defined locations relative to the placement of other content elements at other ones of the defined locations; and placing, with a computer processor, one or more of the content elements at the defined locations within a user interface using the content placement rules.