When I tried upgrading to Intrepid Ibex, I had problems that were annoying enough to go back to Hardy Heron. Unfortunately, I hadn't made a copy of my home folder before the upgrade, so I wound up with config files from both versions. The biggest problem that bothered me was flash being unstable--However, this followed me back to Hardy. I finally deleted the config files and reinstalled Flash to cure it.
I decided to give Intrepid another try, but this time backing up my home folder and doing a fresh install, rather than an upgrade.
So far, so good. Sound worked from the beginning, and I haven't had any problems with flash. Dual screen is working great, and I'm not getting the odd lines from the last time. I've intentionally tried to trigger the keyboard bug, and can't.
The previous instructions for installing XMMS didn't work, but I found this:
It has only been a couple hours, but so far all is well. I'm moving config files over as I need them rather than moving the whole home directory--this way if I have a config issue, I've got a better chance of knowing what it is. It is nice having dual monitors at home, especially since I tend to watch computer video rather than television--I can keep the video on one screen while working on the other.