Moving back to Team system

We've tried them all: post its, Excel, Team system, our own application, Sharepoint, whiteboard. I'm talking about the sprint backlog. And now we're moving back to Team system. Why? Our basic problem is people not updating the sprint backlog. And why are people not updating the sprint backlog? I believe it's because it's not integrated into their daily processes. And why isn't this a part of their daily processes? Because it's not a part of their main focus/application.

I don't believe in tools for solving problems like these. But I want to choose a tool which works as a part of the daily work. At start, we'll just use the MSF for Agile 4 Template which we used when we cheated with MSF For Agile but when we make the transition to VS 2008, we'll install a real scrum template.