If you are not aware of a problem, you cannot fix it.
Having full awareness of the issues and managing it is the key of success for any kind of project (not just software).
For an open-source project it is essential that the issue tracker focuses on at least 3 areas:
Ease of use: You get reports mainly by casual users, they must spend the least amount of time to understand the tool and to provide the information.
Loudness: It must make problems easy to spot.
Data Mining: It should provide tools to query details, aggregate bugs and manipulate them.
Right now I tried in different projects many issue trackers, sadly almost none fit the bill, they usually are actually the opposite: limited, cumbersome, hard to configure and horrible to use either to fill bugs or to actually manage them.
It is by far the least bad, it has plugins to provide near-instant access thanks to Mozilla Persona, it has a rich rpc system that could be leveraged to have irc notifiers or side site statistics, importing-exporting data is almost there. As we know in Gentoo, it requires some deep manipulation and if there is nobody around to do that you can get fallouts like this when a single stubborn (and probably distracted) developer (vapier) manages to spoil the result of the goodwill of another and makes the Project overall more frail.
It is still too rich of confusing option but its default splash views are a boon if you are wondering what’s the status of your project. No open-id/persona/single-sign-on integration sadly.
Usually not good enough on the reporting side and, even if they are much simpler than Bugzilla, still not good for the untrained user. They integrate with the source repository view and knowledge base (aka wiki) so they can be a good starting point for small organizations.
They have a more encompassing approach than redmine and trac, their issue tracker component is too simple in some cases (with Github not having even support for attachments and gogs not really managing tags yet) or a little too rough (no bug dependencies). But, with its immediate UI and the label-oriented approach, it is already pretty good for a large deal of projects. Sadly not Libav: we do need proper attachments.
Request Tracker is overwhelming. No other words. Do not use it if you do not need to. It is too complex to configure on the admin side and is too annoying to use on the developer side. For users the interface is usually a mailbox so you can’t go wrong. Perfect if you have to manage a huge number of paying customer and you want to have detailed billing and other extremely advanced features.
New kid of the block, it is quite simple, way too simple. Its mail rendering makes it not really great but is pretty much a nice concept waiting to bloom. (Will it?)
Do you know any better opensource issue tracker? Please comment down =)