Anyone know of a good command line tool that can dump metadata associated with MP3 files
I don't think anything beats Exiftool for command-line metadata power and versatility. Works in Linux, Windows**, Mac, etc (anything that can run Perl). Works for all kinds of image (very extensive output for digital camera images), video, audio, and other media files.
http://www.sno.phy.queensu.ca/~phil/exiftool/
Here is sample output for OGG, MP3, and MPC
exiftool "Patricia Barber-Companion-Use Me.mpc"
ExifTool Version Number : 6.93
File Name : Patricia Barber-Companion-Use Me.mpc
Directory : .
File Size : 10 MB
File Modification Date/Time : 2006:04:21 17:00:22
File Type : MPC
MIME Type : audio/x-musepack
Total Frames : 15035
Sample Rate : 44100
Quality : 6 (Xtreme)
Max Band : 31
Replay Gain Track Peak : 32949
Replay Gain Track Gain : 65416
Replay Gain Album Peak : 39239
Replay Gain Album Gain : 65161
Fast Seek : No
Gapless : Yes
Encoder Version : 1.1.5
Track : 02
Title : Use Me
Album : Companion
Artist : Patricia Barber
Comment : EAC / MusePack 1.15v --quality 6
Genre : Jazz
Ratesonic : 5
Sub-genre : Jazz
Year : 1999
exiftool "Stone Sour-Stone Sour-Bother.mp3"
ExifTool Version Number : 6.93
File Name : Stone Sour-Stone Sour-Bother.mp3
Directory : .
File Size : 6 MB
File Modification Date/Time : 2006:05:15 19:09:52
File Type : MP3
MIME Type : audio/mpeg
MPEG Audio Version : 1
Audio Layer : 3
Audio Bitrate : 128000
Sample Rate : 44100
Channel Mode : Joint Stereo
MS Stereo : On
Intensity Stereo : Off
Copyright Flag : False
Original Media : True
Emphasis : None
Album : Stone Sour
Artist : Stone Sour
Comment : *** / Foobar2000: MPC->MP3
Genre : Rock
Title : Bother
Track : 08
Recording Time : 2002
User Defined Text : (sub-genre) Alt Metal
Year : 2002
Duration : 0:06:03.67 (approx)
exiftool "Cassandra Wilson-Blue Light 'Til Dawn-I Can't Stand The Rain.ogg"
ExifTool Version Number : 6.93
File Name : Cassandra Wilson-Blue Light 'Til Dawn-I Can't Stand The Rain.ogg
Directory : .
File Size : 8 MB
File Modification Date/Time : 2006:06:16 23:11:36
File Type : OGG
MIME Type : audio/x-ogg
Vorbis Version : 0
Audio Channels : 2
Sample Rate : 44100
Nominal Bitrate : 224000
Vendor : AO; aoTuV b4b [20051117] (based on Xiph.Org's libVorbis)
Comment : EACA/ Ogg Vorbis aoTuV beta4 -q 7
Title : I Can't Stand The Rain
Track Number : 12
Album : Blue Light 'Til Dawn
Artist : Cassandra Wilson
Genre : Jazz
Label : Capital - Blue Note
Ratesonic : 5
Sub-genre : Jazz
Date : 1993
** For Windows, there is a standalone executable that doesn't require Perl to be installed. I use Exiftool mostly in Linux, however.