Just a quick note from an unbiased observer who loves MediaWiki and open-source...
Proprietary or not, Atlassian Jira is the best bug-tracker I have ever used, out of about
10 systems.
- Very configurable
- You can create very simple bug forms for nontechnical users
- Plug-in architecture for developing your own features & modifying app behavior (see
https://plugins.atlassian.com/)
- Helpful reporting capabilities that are easy to use
- Its database schema is pretty understandable so you can extract data directly
- The web interface doesn't do any stupid tricks that break in different browsers
If you're considering another bug-tracker, Jira is worth a look. (I have no
affiliation with the product or the vendor, except as an end-user.)
DanB