Phil Wainewright over at ZDNet makes some very good arguments about the challenges of enterprise mashups in his post Google Maps, the fool's gold of mashups. He begins by noting that nearly two-thirds of the 800+ mashups here are maps mashups and their ubiquity comes from more than their ease of implementation and visual appeal, it comes from the predictability of the data format.
Why does this matter? Because as anyone who has worked in an enterprise IT environment knows (myself included), representation in corporate data is a "semantic minefield". How a Product or Order or Employee is structurally defined varies from department to department, company to company.
As Phil notes -- not nearly as neatly defined as latitude and longitude.