MP3 tags is a way to embed the artist, album, genre, year, etc, etc, etc within the actual MP3 file itself. This way software can read the tag information from each MP3 file it encounters and can build the library hierarchy (ie: load all the songs) accordingly. This way you do not have to have all of your MP3 files in a certain folder format for the jukebox software to load all of the songs. The software will simply read the MP3 tag information from each MP3 file and setup the library automatically.
Anyway, my software does not support MP3 tags.

My software requires all the files to be in a "musicDir/artist/album/song" folder format instead. I personally did not want to take the time to tag all of my MP3 files, plus I have a bunch of video files which can not be tagged so the video files would not get read in automatically anyway. I found it easier to simply have this type of folder format to categorize all the audio/video files. Once you set it up it will be there forever and it helps to load the music and regenerate the library (when you add new songs) rather quickly. Also, whenever you add new songs you do not have to first edit the MP3 tag information for each new song, you simply have to put it in the correct folder and that is it.
Just go to my site and read the FAQ for exact descriptions of everything.
Feel free to ask questions here of course, although I am going away for a week on vacation so I will not be around to answer stuff in the short term.
PS: To answer your question, if you choose to use other jukebox software for your jukebox because you want to use MP3 tags then I think "Tag and Rename" is software which has been mentioned a few times around here. Although your best bet is to simply ask for the best MP3 tag editor within the Audio/MP3/Jukebox forum.