I've used Streber [streber-pm.org] with success at previous positions for software dev management. It's open source, ajaxy, and supports a nice granularity of task views depending on milestone driven organization or task priorities. It's integrated with wiki and has a homegrown version control system for file attachments (which I could care less about). There may be integration with subversion now, I have not updated it in a while. The biggest complaint I see people mentioning so far is a lack of a Gantt chart, that's a design choice by the primary developer. One other thing is that the pace of development can be quite slow, since there are few developers on board (or at least there were).
However, reading what I'm seeing here, I will have to give opengoo a shot.