These errors appear in the upgrade logs after a configuration of SP1 and the corresponding June CUs of SharePoint Server 2010.
ERR The exclusive inplace upgrader timer job failed.
ERR An exception of type Microsoft.SharePoint.PostSetupConfiguration.PostSetupConfigurationTaskException was thrown. Additional exception information: Failed to upgrade SharePoint Products.
Microsoft.SharePoint.PostSetupConfiguration.PostSetupConfigurationTaskException: Exception of type 'Microsoft.SharePoint.PostSetupConfiguration.PostSetupConfigurationTaskException' was thrown.
ERR Task upgrade has failed
I completely ignored these errors and just ran the configuration a second time on each front end. Magic. I am sure if I devoted time to this I could figure out what happened. If someone knows, feel free to comment. I didn't want to devote any time to figuring out an error that I moved past so easily.