Just tried that tonight (www.id3-tagit.de that is), and I think overall that I (well, I would) like it better than MP3 Tag Studio.

But - though it looks like you can highlight a list of songs, and change many tags with only one entry, it won't "save" them. It will ask me, and I'll click yes, and it will ask again. After about 20 presses on the "yes" button, I gave up. Reinstalled it, rebooted, etc, no change. Something I'm missing here? Otherwise I'm inclined to think "nice idea, too bad it doesn't work".