Project management tools

We're looking for a new project management system at Hotchalk so I've been evaluating what's available in the online arena.

Basecamp
The old and trusted tool but it's lack of a ticket management system is unacceptable for our needs. Since it has an API I hoped to find a ticket tracking app that would create tasks in basecamp and provide some nice integration. The only tool I found was http://bctix.com. While it boasts integration with basecamp BCTix is half baked and not ready for prime time.

Trac
A great tool for defect management and I was disappointed to find there are no plugins to basecamp. Trac has great plugin support but I suppose all those python guys are still bitter about the popularity of Ruby and are not in a hurry to contribute to 37 signal project.

Goplan
It's like basecamp with a few more features. It does have ticket management, but it's so minimal I don't really see the benefit. My major complaint is the inability to link tickets to a milestone or release. This is huge, without it there is almost no difference between tickets and the messages available in basecamp. On the plus side it's stable, and is a viable substitute for Basecamp.

Lighthouse
This is going to be the tool to watch. It is more issue tracking centered and has all the standard API's. It also allows you to create and update tickets via email, which is great for people on mobile devices or just to lazy to log in. It lets you associate tickets with milestones and shows a nice status bar as you close all the tickets related to a milestone.