Add ogg support to iTunes on Mac OS X

iTunes for Mac:
this was harder to find than I thought.
Not hard, just not trivial; this should be a one-click add-capability type action,
but the instructions were not as clear. (Ideally, iTunes would already have support for open formats.)

1. Quit iTunes
2. Download XiphQT QuickTime component.
   This is a small 1M .dmg; double click to open it. You'll see some text files, but most importantly
   XiphQT.component
   
3. Copy it in to /Library/QuickTime
4. [Optional] This is only necessary if you want to double-click an .ogg file and have it open in iTunes. You can still use the 'add to library' menu item or drag files from the Finder on to iTunes. I think.
   Edit the info.plist file inside of iTunes;
   see instructions here: http://en.wikibooks.org/wiki/Using_iTunes/Ogg_in_iTunes
   

Go to dir.xiph.org and try an ogg stream.
Start up iTunes and play.
I did this on 10.6.4.