While this article is not new (was published in October 2006), and you can purchase it from http://www.gartner.com/DisplayDocument?id=497386&ref=g_sitelink, I thought it might be of value to quote (and paraphrase) a few key points:
1. “In most successful agile efforts, business staff … constitute between 10% and 25% of the [total project] staff”
2. In agile development (AD), you don’t fund a project, but rather project development. The difference being that there is no delivery date or even an agreed upon list of functionally, but rather an agreement for the business people and IT to work together and re-evaluate the level of staffing going forward on a regular bases and based on what’s been delivered thus far and the desired functionality to be built.
3. Following agile development practices do not relieve you from doing design and modeling. To be successful, especially when developing large, high-scalability applications with service-level requirements, the team should “incorporate standard modeling techniques”.
4. Agile does not mean lack of process consistency. Structure is an important factor for success in AD.