We use Pivotal Tracker to manage our agile development at an airline. We love the open nature of the tool, in that it only presents the bare bones of what you'll need and then you can make it work in any way you want. We also like the dynamic nature of the real-time updates. I can watch my browser window update to reflect the work in process.
The tool has been extremely robust. They notify us well in advance of outages, both on their site and via twitter.
The most important item for gaining acceptance of the tool is that we can export our work from the tool into .csv so we can continue to work if Pivotal goes offline.
We use Pivotal Tracker at Kongregate and love it. You can do everything from one screen. It's got a great lightweight approach to iterations and velocity tracking - once you've done a few iterations you get surprisingly accurate estimates of when you'll deliver that next release. It's both more pleasant to use and more suited to our needs than a straight ticketing system.
We use Basecamp to discuss features & comps, then Tracker to get them done. Trying to use Basecamp for both doesn't really work if you care about iterations, story points, etc. Some might say you don't need those, but they've given us a lot better predictability than we did at first.
The tool has been extremely robust. They notify us well in advance of outages, both on their site and via twitter.
The most important item for gaining acceptance of the tool is that we can export our work from the tool into .csv so we can continue to work if Pivotal goes offline.
Highly recommended.