Grouping files: directories or tags?
A big difference between Subsonic 4.7 and MusicCabinet is how files are grouped into albums.
Subsonic is mostly directory based. If you have a lot of files in one directory, they're seen as one "album".
MusicCabinet, on the opposite, does not use a directory based approach. Instead, files are grouped based on tags. You can have multiple files from the same album in different directories (for example CD1 and CD2), and they're still grouped as one album by one artist.
This, however, presents a problem for people who have badly tagged compilation albums (like "Summer Hits 2012"). Sometimes, there's just a bunch of files by different artists, placed in the same directory to indicate that they're one album. MusicCabinet will interpret these files as different albums, as they all have different artist names.
Using the Album Artist tag
To tell MusicCabinet that these files are all one album, you have to use the "Album Artist" tag (TPE2 in ID3 v2). By setting the "Album Artist" tag to "Various Artists" for all songs from the compilation album, it'll be seen as one album, and appear in the left frame as "Various Artists". When the album is displayed, individual artist names per song are shown, scrobbled to last.fm, and can be searched for.
The same goes for hip-hop albums where there's one main artist, but the single songs have different performers, like X feat Y, X feat Z, etc. To have such an album grouped as artist X in the left frame, set "Album Artist" tag to X for all songs.
Artist view includes tracks from compilation albums
When selecting an artist from the left frame, both full albums and single songs from compilation albums are displayed. Here, there's one full album by artist Moneybrother, and one song ("Morbror Frans") found on a compilation album. http://i.imgur.com/Hw4aH.png
Only artists with full albums are shown in the left view, to avoid having it scattered with "one hit wonders".