Howdy all!
I was experiencing this exact issue during testing of our OSD in SCCM 2012. I ran through a premiere support call with MS and quite a bit of troubleshooting before determining the cause.
Reference to issue in SCCM 2007
Essentially, this issue is still present in SCCM 2012. During an OSD process, the SCCM client may get "stuck" in provisioning mode. I found that my OSD would complete and the client would register correctly with one task sequence, but if the application installation order changed, the client would get stuck in provisioning (no self-signed cert). Odd that the application install would affect the "Setup windows and config manager step....
As mentioned in the blog article - checking the registry keys will identify if the client is getting stuck or if your issue is possibly caused by another factor. I have included the following at the end of my task sequences to ensure that clients will always register (or at least until the problem is fixed by other means.....*cough* SP1 *cough*)
(taken from email exchange MS Engineer)
Right after the "Setup Windows and ConfigMgr" step, add two "Run Command Lines" to set the registry values correctly. Here are the two commands to be run:
REG ADD HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\CCM\CcmExec /v ProvisioningMode /t REG_SZ /d false /f
REG ADD HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\CCM\CcmExec /v SystemTaskExcludes /t REG_SZ /d "" /f
Please let me know if this helps at all....