InfoQ did an interview with Menno Vis, IT director of bol.com, about the benefits of increasing agility, how bol.com deploys Scrum, using roadmaps with agile, the challenges that have been faced when scaling agile, the main focus area's at bol.com for agile scaling, establishing loosely coupled teams, and the things that bol.com does for their people to have fun while doing their work.
Scott Sehlhorst, product management and strategy consultant describes two views of the product roadmap.
Experimentation using for instance lean startup can help you learn about your customers and find out which features and product would be valuable. The value however comes from building products and actually delivering them to customers. You need to find ways to balance between experimentation and delivery.