Description of problem:
A dialog popped up asking me to report an "internal system error".  It didn't say what to report it against, but given the backtrace, I'm guessing PackageKit.  Here's the backtrace:

Traceback (most recent call last):
  File "/usr/share/PackageKit/helpers/yum/yumBackend.py", line 2095, in get_distro_upgrades
    pkgs = self.yumbase.pkgSack.returnNewestByName(name='preupgrade')
  File "/usr/lib/python2.6/site-packages/yum/__init__.py", line 649, in <lambda>
    pkgSack = property(fget=lambda self: self._getSacks(),
  File "/usr/lib/python2.6/site-packages/yum/__init__.py", line 491, in _getSacks
    self.repos.populateSack(which=repos)
  File "/usr/lib/python2.6/site-packages/yum/repos.py", line 260, in populateSack
    sack.populate(repo, mdtype, callback, cacheonly)
  File "/usr/lib/python2.6/site-packages/yum/yumRepo.py", line 162, in populate
    if self._check_db_version(repo, mydbtype):
  File "/usr/lib/python2.6/site-packages/yum/yumRepo.py", line 220, in _check_db_version
    return repo._check_db_version(mdtype)
  File "/usr/lib/python2.6/site-packages/yum/yumRepo.py", line 1178, in _check_db_version
    repoXML = self.repoXML
  File "/usr/lib/python2.6/site-packages/yum/yumRepo.py", line 1342, in <lambda>
    repoXML = property(fget=lambda self: self._getRepoXML(),
  File "/usr/lib/python2.6/site-packages/yum/yumRepo.py", line 1338, in _getRepoXML
    raise Errors.RepoError, msg
RepoError: Cannot retrieve repository metadata (repomd.xml) for repository: updates-debuginfo. Please verify its path and try again

As a matter of fact, I do have updates-debuginfo installed.  Doing a "yum upgrade" also chokes, thusly:

# yum upgrade
Loaded plugins: refresh-packagekit
fedora/metalink                                          |  27 kB     00:00     
fedora                                                   | 3.8 kB     00:00     
fedora/primary_db                                        |  10 MB     01:30     
fedora-debuginfo/metalink                                |  21 kB     00:00     
fedora-debuginfo                                         | 2.7 kB     00:00     
fedora-debuginfo/primary_db                              | 1.2 MB     00:02     
updates/metalink                                         | 4.3 kB     00:00     
updates                                                  | 4.4 kB     00:00     
http://fedora.univ-nantes.fr/fedora.redhat.com/fedora/linux/updates/11/x86_64/repodata/repomd.xml: [Errno -1] repomd.xml does not match metalink for updates
Trying other mirror.
updates                                                  | 4.4 kB     00:00     
http://ftp.fi.muni.cz/pub/linux/fedora/linux/updates/11/x86_64/repodata/repomd.xml: [Errno -1] repomd.xml does not match metalink for updates
Trying other mirror.
updates                                                  | 4.4 kB     00:00     
http://ftp.linux.cz/pub/linux/fedora/linux/updates/11/x86_64/repodata/repomd.xml: [Errno -1] repomd.xml does not match metalink for updates
Trying other mirror.
ftp://ftp6.linux.cz/pub/linux/fedora/linux/updates/11/x86_64/repodata/repomd.xml: [Errno 4] IOError: <urlopen error [Errno -2] Name or service not known>
Trying other mirror.
updates                                                  | 4.4 kB     00:00     
ftp://alviss.et.tudelft.nl/pub/fedora/linux/updates/11/x86_64/repodata/repomd.xml: [Errno -1] repomd.xml does not match metalink for updates
Trying other mirror.
updates                                                  | 4.4 kB     00:00     
http://fedora.uib.no/fedora/linux/updates/11/x86_64/repodata/repomd.xml: [Errno -1] repomd.xml does not match metalink for updates
Trying other mirror.
updates                                                  | 4.4 kB     00:00     
http://ftp.df.lth.se/pub/fedora/linux/updates/11/x86_64/repodata/repomd.xml: [Errno -1] repomd.xml does not match metalink for updates
Trying other mirror.
updates                                                  | 4.4 kB     00:00     
http://ftp.informatik.uni-frankfurt.de/fedora/updates/11/x86_64/repodata/repomd.xml: [Errno -1] repomd.xml does not match metalink for updates
Trying other mirror.
updates                                                  | 4.4 kB     00:00     
http://ftp.gui.uva.es/sites/fedora.redhat.com/linux/updates/11/x86_64/repodata/repomd.xml: [Errno -1] repomd.xml does not match metalink for updates
Trying other mirror.
Error: Cannot retrieve repository metadata (repomd.xml) for repository: updates. Please verify its path and try again

Version-Release number of selected component (if applicable):
PackageKit-0.4.8-1.fc11.x86_64

How reproducible:
Always (today).  I expect that when the underlying repo issue is resolved, I will no longer be able to reproduce.

Steps to Reproduce:
1. Wait for PackageKit to attempt an update.
  
Actual results:
Dialog box reporting an internal system error.

Expected results:
Some more graceful way of handling hosed repo mirrors.

Additional info: