Some actual data here:

• Alpha1 (staged) build took 2:05 to install on my machine
• Alpha1 nightly (B5370) took 5:15 to install

Around the minute mark the installation just freezes in this state:

Meanwhile the trace says:

Committing the provisioning operation.
Operation completed in 275702 ms.

That is quite a long time it spent doing that operation.

Some jstack info can be found here:
http://pastebin.test.redhat.com/374700