Given my success with Ubuntu 11.04 on the BeagleBoard, I decided to take a shot at dual booting an older iMac (late 2007 24" Core 2 Duo a.k.a. iMac7,1) into 11.04.

(Note: a handy way to determine the model of your Mac from the Linux command line: sudo dmidecode -s system-product-name)

I mainly followed the instructions found here and am just noting the things I ran into on my particular Mac.

First, I had to get rEFIt installed to allow for selecting which partition to boot into. Installation boiled down to installing the .mpkg and then running /efi/refit/enable.sh

Next, I had to get an 64-bit install image for Mac systems. The standard 64-bit install image apparently has problems on Macs (EFI?) and the Natty download page has an alternate 64-bit image available.

After going through the install process, I was pleasantly surprised by how well things were working. I expected a lot of problems with missing device drivers given how closed Apple is about these things. This was not at all the case as the majority of the hardware was properly detected and configured automatically.

Of course there are a few of issues to deal with such as:

1. While the sound drivers were working, the audio out of the system was tinny. Fortunately, this is a known issue and the fix was to add options snd-hda-intel model=mb31 power_save=10 power_save_controller=N to /etc/modprobe.d/alsa-base.conf. This greatly improves the audio quality though it still sounds a bit harsh compared to the audio produced under OS X.
2. The microphone input was unselected and muted after installation. Going to Preferences->Sound->Input, selecting 'Internal Audio Analog Stereo', and unmuting took care of that issue.
3. Support for the iMac aluminum keyboard USB ports seems a bit flakey. A couple of my devices that work fine under OS X aren't working properly under Linux. For example, I am able to connect my tablet to the keyboard USB port under OS X with no problems, under 11.04 it doesn't work and there are log entries indicating that the port doesn't have enough power. No big deal as the devices in question can be moved to other ports.
4. Occasionally, external hard drives connected via USB will become unresponsive with "kernel: ... reset high speed USB device using ehci_hcd and ..." messages. The solution found in a couple of Google searches was basically 'change the controller and/or drive' which wasn't really an option for me. While a bit of an annoyance, I've experienced similar problems in the past with OS X and USB hard drives on this machine so the problem will be avoided by connecting drives via Firewire whenever possible.

I've installed Linux on name brand PC's that had more, and more serious, driver issues than that.