taghycardia

Pros:

(+) quick auto tagging

(+) easy to use: conveniently prompts on any tag faults like missing album/artist, often offering the right info guessed from existing clues such as folder name or tags present in part of the tracks

(+) fast auto cover art discovery due to using both local and online images

(+) does not require Java or .Net

Cons:

(-) auto track title correction possible only by supplementing filenames for missing track names (though cuts out unneeded info from the filenames)

(-) no custom rename option

(-) working with the internal manual tag editor is not quite well documented (but when you puzzle it out, it really helps with some tasks like getting art for the albums the program couldn't find a cover automatically)

Summary

This free utility comes in handy when you need to make sense of a bunch of albums you just downloaded. Like, you unpacked some archives into some folders with random names, and you want to upload them to your iPhone clearly tagged. So you run your folders through taghycardia, and some seconds later voila, they are named Artist - Album (Year), and have right tags complete with embedded cover art.

I also tried to use this to auto-tag some part of my hdd mp3 library; taghycardia produced mostly good results, too. Maybe it lacks some features, but its strengths are definitely speed and ease of use.