If you don't like the way Itunes handles files for you, then Cog is the solution. I love cog - it's simple and it just works.

There's an interesting discussion about audio players for Mac OS X on hydrogenaudio.

the latest nightly/development build fixes the bugs discussed below. it can be downloaded from here; http://cogx.org/nightly_builds/Cog-r519.tbz or installed through cog's integrated sparkle-based updating system.

Note: if Cog crashes on opening because of a dead file in its playlist, it'll crash everytime you open it. To solve this, you have to be quick: open Cog and while the playlist is loading, do a cmd-a to select all, then backspace to empty the playlist, then close Cog. If you're fast enough, this should work. :)

v. 0.06 crashes on opening in case a file in the playlist can't be found (ie: it has been moved or deleted.)
It also crashes when adding some Flac files to the playlist, not sure why.
But still, it's a good and very promising audio player! :)

@ xaphirezst:
Tag is a nice metadata editor for FLAC, Ogg Vorbis, Monkey's Audio and WavPack files.
You'll find Tag here:
http://osx.iusethis.com/app/tagmetadataeditor

I wonder if I can change audio tags with this?

new release, 0.06 stable, grab it at; http://www.cogx.org

people, people, try out the latest development releases... cog only gets better and better.

@bitnix:

I agree, those are features that should be implemented, but notice the version: 0.0.5---still got a long ways to go! Be patient :)