Yosemite upgrade frozen, what should I do? I'm trying to upgrade a Macbook Pro to Yosemite. It downloaded everything just fine, restarted the machine into the installer process. That went just fine until it just stopped.

It's on the "Installing on 'Macintosh HD'" screen with a progressbar sitting at around 60% and says "About 29 minutes remaining". It's been sitting in that same spot for over two hours now.

Does anyone have any advice on what to do at this point?

UPDATE: I ended up holding down the power button to halt the machine, turned it on again, and hoped that it would start okay. It did. :)  It just appeared to restart the install process, and everything was fine. It got to the last minute or so and took quite awhile, but it did finish.

Apparently having Homebrew installed, or something else which stores a bunch of files in /usr/local, will cause this last-minute slowdown of the installer. You can either move those files before you install or you can just wait it out during the last minute.

I'm really not sure what caused the installer to halt at the 29 minute mark. But just turning it off/on did not hurt anything.
As recommended by 0942v8653, Command+L will show you the log and give you a better idea what is going on. In my case, the delay was due to copying of TexLive that had an enormous number of files.