The problem appears to be related to libasound2:i386 and its dependencies. These packages are depended on by skype, so that is why I use them. There is a conflict between some of them, and the other packages (gimp, ffmpeg, vlc, kaffeine, etc.) that were pulled out. It looks like dmo has a newer version of libavcodec55:i386, but not of libavcodec-extra-55:i386, so that is apparently holding up the show. Here's the apt-get output, FYI:
root@imerabox:/# apt-get install libasound2-plugins:i386
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
libasound2-plugins:i386 : Depends: libavcodec55:i386 (>= 6:10~beta1~) but it is not going to be installed or
libavcodec-extra-55:i386 (>= 6:10.1) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
root@imerabox:/# apt-cache policy libavcodec55:i386
libavcodec55:i386:
Installed: (none)
Candidate: 10:2.2.2-dmo1
Version table:
10:2.2.2-dmo1 0
500 ftp://mirror.csclub.uwaterloo.ca/debian-multimedia/ unstable/main i386 Packages
6:10.1-1 0
500 http://ftp.us.debian.org/debian/ unstable/main i386 Packages
6:10-2 0
1 http://ftp.us.debian.org/debian/ experimental/main i386 Packages
root@imerabox:/# apt-cache policy libavcodec-extra-55:i386
libavcodec-extra-55:i386:
Installed: (none)
Candidate: 6:10.1-1
Version table:
6:10.1-1 0
500 http://ftp.us.debian.org/debian/ unstable/main i386 Packages
6:10-2 0
1 http://ftp.us.debian.org/debian/ experimental/main i386 Packages
root@imerabox:/# apt-get install libavcodec55=6:10.1-1
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following package was automatically installed and is no longer required:
libx265-13
Use 'apt-get autoremove' to remove it.
The following packages will be REMOVED:
browser-plugin-vlc ffmpeg gimp kaffeine libavdevice55 libavfilter4
libavformat55 libgegl-0.2-0 libgimp2.0 libxine2-ffmpeg libxine2-plugins
libxine2-x phonon-backend-vlc vlc vlc-nox vlc-plugin-notify vlc-plugin-pulse
xine-ui xsane
The following packages will be DOWNGRADED:
libavcodec55
0 upgraded, 0 newly installed, 1 downgraded, 19 to remove and 0 not upgraded.
Need to get 2,806 kB of archives.
After this operation, 47.7 MB disk space will be freed.
Do you want to continue? [Y/n]
Edit: I commented out the dmo source, and was able to reinstall skype's dependencies, and then skype. I can live without gimp and the others for awhile, until the conflicts are resolved.