Additional Metadata and Information

Some information cannot be stored in the MusicBrainz database but is important background information for editing and voting. These are:

IdenticallyNamedArtists - A list of artists who have the same name. Most of them are not yet SplitArtists but are one entry in the database so you could start to work on them.
NotDuplicateArtists - This tries to keep track of artists with similar names who are not duplicate entries and should not be merged. Also see NotDuplicateAlbums for a list of similar albums which are not the same.
OddReleases - Different releases that are hard to fit into the MusicBrainz schema.
- There is also a page called OddReleaseDiscussion. It is rather outdated and if you have a question when editing something odd it is probably best to ask in the UsersMailingList or see if you find a hint in the StyleGuidelines.

InternationalArtists - Lists of artists from certain countries. This is a good point to start editing on artists in your native language! Also if you want to keep track on the artists from a certain (your) country you can subscribe to the artists on this list.
- If you need help editing in certain languages you might want to look at TellSimilarLanguagesApart of contact a moderator with a certain ModeratorLanguage - or you try one of the OnlineTranslators.

External

OtherDatabases can be helpfull resources for editing the data in MusicBrainz.
A rather outdated page provided links to ArtistDiscographys - though now that they can be stored using AdvancedRelationships this page only contains a few usefull links.
Again: there is a list of OnlineTranslators.

Trivia is the fun in data!

For attempts to collect trivia about the data stored in the MusicBrainz database see DataTrivia.
But there is also information about the social component of it: MusicBrainzSlang for example tries to describe vocabulary used by the MusicBrainz users.

Storing subjective, non-factual data maybe one of the future goals of MusicBrainz. As by now there are only proposals.

There is a very outdated draft for MusicReviews but this is not used anymore. Though we have a new separate Wiki dealing with questions about the realization of a review system: http://review.musicbrainz.org/.
EditorRating might provide means of rating the data in MusicBrainz.
Genre information is perhaps too subjective and may lead to disputes (see GenreAlternative for another outdated draft) but the data could be categorized using a FolksonomySystem.