It's not the latest sequel to the 'Jason versus Freddie' movie, it's one of the decisions you need to make if you're rolling out a Web 2.0 product. Make the wrong choice, and your project and reputation can suffer. Make the right choice, and you can be a hero. There aren't any easy answers, but I can take you on a tour of the technology and the decisions involved so you can make a better-informed choice. During our tour I promise you won?t be attacked by a man in a hockey mask, so sit back and enjoy the ride.