VDP: Web-to-Print In the Real World

What is the extent of the functionality that users require? How much flexibility must printers build into the system to accommodate future, as well as current, needs? What if their client base changes? What is the balance between anticipating future needs and what they can afford to invest now? What if printers need additional capabilities down the road, but because they already sunk so much into their existing system, they can’t afford to expand or upgrade?