After a few days of heavier use I'm still really enjoying this thing. I do wish it had more specific, dedicated "project planning" functionality, e.g. enter in a series of high-level tasks with sub-tasks, due dates, etc. but you can use the issue tracker roughly that way, including scheduling, basic gantt-type charting, etc. Of course there are probably plugins that would help accomplish this, but I haven't delved into them too much yet: http://www.redmine.o.../redmine/Plugin_List
Just thought I'd also mention, for anyone who doesn't have a web server, doesn't want their data to live on someone else's machine, or just wants a quick and easy way to set this up at home for their own use, Bitnami has a Redmine stack that works very well: http://bitnami.org/stack/redmine
Bitnami basically allows you to install and run Redmine (and many other web-based tools) automatically and easily on your local machine, without worrying about getting all the necessary supporting apps - Apache, Ruby on Rails, etc. Then you just access it locally on your machine through a web browser, easy as pie.