Comment 4 for bug 947664

The build is a stock Lubuntu Precise installed one its own, taking up the whole disk with no special partitioning or formatting options. It's an 8GB expandable virtual disk provided by Oracle Virtualbox.

It's hard to tell for sure what the process is which is taking so long. It could in principle be some kind of build step, but if this is the case, something should be shown at the console, else reporters have to assume it's the 'unpacking' step as indicated.

The process did eventually complete. I'll see if I can recreate the next time I do an update and carry out the diagnostic steps you describe.