It certainly gives a huge boost to distributed teams. But another big reason is tracking and reporting even on co-located teams. It's nice to have a single place to capture requirements, estimates, actuals, priorities, issues, risks, etc. This makes it easy to generate status reports for the various stakeholders and easily keeps everyone on the same page. There are many tools out there already that do this. But many teams don't like to use them because they go against the grain of how they like to work. As soon as the tool gets in their way the team slows down and eventually they will stop using it altogether (or use it only when their manager forces them to). If it slows them down, they get less work done. If they stop using it, the data in the tool falls out of synch with the "data" in the team room. Either way, it's not great. So our goal is to make Mingle the tool that teams using big visible charts, story walls, etc. actually want to use. This of course means it has to mold to the way they want to work.