Thanks for your report.

This is because the upgrader decides to replace libpostproc52:i386 by libpostproc52:amd64 and fails because they are not co-installable and dpkg thinks i386 is still installed while it has been removed earlier.

The relevant parts of term.log are:
Removing libpostproc52:i386 (6:0.8.10-0ubuntu0.13.10.1) ...
Processing triggers for libc-bin (2.19-0ubuntu6) ...
--
Unpacking libmtp9:amd64 (1.1.6-20-g1b9f164-1ubuntu2) over (1.1.6-2) ...
dpkg: error processing archive /var/cache/apt/archives/libpostproc52_6%3a0.git20120821-4_amd64.deb (--unpack):
 libpostproc52:amd64 6:0.git20120821-4 (Multi-Arch: no) is not co-installable with libpostproc52 which has multiple installed instances
Preparing to unpack .../libssh2-1_1.4.3-2_amd64.deb ...
--
Errors were encountered while processing:
 /var/cache/apt/archives/libpostproc52_6%3a0.git20120821-4_amd64.deb
dpkg: tk-lib:amd64: dependency problems, but removing anyway as you requested:
--
Setting up libmtp9:amd64 (1.1.6-20-g1b9f164-1ubuntu2) ...
dpkg: error processing package libpostproc52:amd64 (--configure):
 package libpostproc52:amd64 is already installed and configured
Setting up libssh2-1:amd64 (1.4.3-2) ...
--
Errors were encountered while processing:
 libpostproc52:amd64


And from main.log
     MarkDelete xserver-xorg-glamoregl [ amd64 ] < 0.5.1-0ubuntu4.2 > ( x11 ) FU=0
  MarkInstall libpostproc52 [ amd64 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) FU=0
   Removing: libpostproc52
    MarkDelete libpostproc52 [ i386 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) FU=0
  MarkInstall libpostproc52 [ i386 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) FU=0
   Removing: libpostproc52
    MarkDelete libpostproc52 [ amd64 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) FU=0
  MarkInstall libfftw3-3 [ amd64 ] < 3.3.3-5ubuntu1 -> 3.3.3-7ubuntu3 > ( universe/libs ) FU=0
--
  MarkInstall gstreamer0.10-ffmpeg [ amd64 ] < 0.10.13-5 > ( libs ) FU=0
  Installing libpostproc52 as Depends of gstreamer0.10-ffmpeg
    MarkInstall libpostproc52 [ amd64 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) FU=0
     Removing: libpostproc52
      MarkDelete libpostproc52 [ i386 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) FU=0
  MarkInstall gstreamer0.10-ffmpeg [ i386 ] < 0.10.13-5 > ( libs ) FU=0
  Installing libpostproc52 as Depends of gstreamer0.10-ffmpeg
    MarkInstall libpostproc52 [ i386 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) FU=0
     Removing: libpostproc52
      MarkDelete libpostproc52 [ amd64 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) FU=0
  MarkInstall rsyslog [ amd64 ] < 5.8.11-2ubuntu4 -> 7.4.4-1ubuntu2 > ( admin ) FU=0
--
  Fixing ubuntu-drivers-common:amd64 via remove of jockey-kde:amd64
Investigating (0) libpostproc52 [ amd64 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs )
Broken libpostproc52:amd64 Conflicts on libpostproc52 [ i386 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs )
  Considering libpostproc52:i386 1 as a solution to libpostproc52:amd64 5
  Added libpostproc52:i386 to the remove list
  Conflicts//Breaks against version 6:0.8.10-0ubuntu0.13.10.1 for libpostproc52 but that is not InstVer, ignoring
  Fixing libpostproc52:amd64 via remove of libpostproc52:i386
  MarkDelete libpostproc52 [ i386 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) FU=0
Investigating (0) tcl [ amd64 ] < 8.5.0-2ubuntu5 -> 8.6.0+6ubuntu3 > ( interpreters )
--
Investigating (0) gstreamer0.10-ffmpeg [ i386 ] < 0.10.13-5 > ( libs )
Broken gstreamer0.10-ffmpeg:i386 Depends on libpostproc52 [ i386 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) (>= 4:0.8-1~)
  Considering libpostproc52:i386 1 as a solution to gstreamer0.10-ffmpeg:i386 -1
Broken gstreamer0.10-ffmpeg:i386 Depends on libpostproc-extra-52 [ i386 ] < none > ( none ) (>= 4:0.8-1~)
  Or group remove for gstreamer0.10-ffmpeg:i386

This is reproducible