Library-based music players are great. They let you use all sorts of data to tweak your listening habits, or to find the song you want, or to help make sure you don't downloadbuy a song twice by accident. But aside from the data that can be automatically generated like how many times it's played a track, or when the last time was, metadata has to come from somewhere. I don't know of any online sources that provide the richness of data that I want, whether I purchase the track on disc or online. Most of the time I have to tag tracks myself. Here's a quick history of the ways I've done it before Quod Libet.
When I first started ripping my collection in the late 1990s, WinAmp was the pinacle program; MusicMatch Jukebox was a helpful ripper with its own ambitions. I would rip a CD with the latter, and then fix up its tags with the former. Tag editing was limited to ID3v1 and the state of the art tag editor was a simple form allowing me to specify a Title, an Artist, an Album, a Comment, a Genre, a Year and a Track number. If I wanted to edit all the tracks of an album, I had to duplicate the information across the tracks manually.
I believe MusicMatch worked differently and would actually allow me to specify some of these items in bulk. However it would append its own frame to the end of a song, effectively overwriting the real
ID3 tag, and when an ID3 tag was appended, it couldn't find its frame. Yes, ID3 tags are a hack. At this stage they weren't even an elegant hack, and intercompatibility wasn't ready.
Some years later I used the free software equivalents: XMMS and grip. Grip would query CDDB or FreeDB for track information, and automatically add it to an encoded MP3 or Ogg Vorbis track. Thankfully there was no extra frame conflict; ID3v1/ID3v2 had become standard for MP3s by this time, and Ogg Vorbis had its own comment standards. Now that the tools agreed, they worked together well. When CDDB had all the information correct there was no editing work to do; when it did not, grip allowed me to edit it before ripping. The interface was similar to WinAmp's in that there was a form with several entries, but since grip shared items such as Artist and Album, it saved a lot of copy and paste.
Not all my albums had good coverage on CDDB. One frequent problem would be spelling and accents for unusual names. After one session, half of my discs had been ripped under artist Moxy Fruvous
and half under Moxy Früvous
. Other times I would want to change storage conventions, or learn new information that meant my previous tags were wrong. Or I started using Rhythmbox and wanted more informative tags—it's too bad that Rhythmbox is only now starting to get editing capabilities.
At this point grip would be no help unless I were to re-rip and re-encode the tracks, so I turned to cantus. Cantus was the first program I used to rename files based on their tags, or retag files based on their names. Unfortunately cantus was tuned for MP3 with ID3v1 style ID3v2 tags, and was extremely buggy in the version that added support for Ogg Vorbis. I'm sure it's fixed by now, but I've never looked back. Cantus among others never really handled arbitrary tags very well, instead they handled only the ID3v1-esque predefined set.
When Joe started writing Quod Libet, I knew it was time to bring all the pieces together. I needed good support for converting between filenames and tags, and i needed great ways to apply the same changes to several songs at once. Many programs (the command-line id3v2 tool) would allow you to apply certain changes (setting the artist) to several tracks, but would not support symmetric operations (removing a comment). I would make Quod Libet support doing both at once. As other time-savers became obvious Joe would add them. At this point I'm comfortable saying that Quod Libet's tag editing is top notch. I hear EasyTag is good, but I can't imagine anything actually being better than Quod Libet for how I use it.