Kernel panic at shut down
Both panic logs indicate the panic happened in the org.openafs.filesystems.afs extension, so that's the logical suspect.  The OpenAFS page for Mac OS X seems to indicate that version 1.6.0 is current, and lists separate installs for different versions of OS X. Your panic logs indicate you have 1.6.0fc7, which is presumably a final candidate, not the actual release.  I'd disable the extension first, then try installing the current Lion version.