The reason for the increase in the major version numbering from 2 to 3 so soon after version 2 was released it that this a very significant release that now does all the MusicBrainz searching from our Jthink Music server rather than MusicBrainz itself.
Jthink Music serverThe Jthink Music server is not simply an exact copy of the MusicBrainz server, it is built from the same MusicBrainz database but provides a new api customized to provide exactly what is required for SongKong to do optimal matching. Because SongKong can now get the information it needs with many less queries the performance testing done so far has seen an 800% improvement in performance, to put it another way what used to take 3 hours now takes just over 20 minutes.
Sort ArtistThe Jthink Music Server contains both MusicBrainz and Discogs data allowing us to share information something that is not possible if connecting directly to the MusicBrainz or Discogs server alone. For example MusicBrainz artists always contain a sort name, so the artist Kate Bush has a sort name of Bush, Kate, but Discogs does not store sort names. Previously, this meant if a release could only be matched to a Discogs release but not a MusicBrainz release the sort artist would no be set, now as long as the artist is in the MusicBrainz database the sort artist will be set for a Discogs only match.
Original ReleaseA popular feature of SongKong is its ability to find the original release and date of a song, that is the earliest release the song could be found on. With the MusicBrainz api this was difficult to work out because different things had to be checked to find the earliest release such as other releases within release group, all releases that the recording is found on, and all releases for recordings withe same acoustid and name as the recording. It was so complicated it wasn't always possible to find the earliest release, but now the earliest release is pre-calculated for every song, so can always be returned for every song.
There are also a host other bugs and improvements in this release, see here for full details