I currently use kid3 myself nowadays. There's a -qt version if you don't need the full kde integration.
I like many of the editing features of easytag, particularly the find/replace tools, but I don't like the way it always wants to autoload/autocorrect everything for you. Also, it doesn't allow the manipulation of arbitrary tags and the interface is a bit clunky to use.
Not that kid3 doesn't have its weak points too, of course.
I also find myself using the cli vorbistagedit a lot these days. Simple, direct access to the tags in your favorite text editor. Very nice. As you can guess from the name though, it doesn't support id3.
BTW, as a kind of side-tangent, if you haven't seen mp3diags
yet, I heartily recommend it. It did a superb job cleaning up all the crappie mp3's in my collection. Be sure to read all the documentation first!