Ok after unleashing a bunch of frustrations on the java-seed apple list this afternoon, I had a little dead time and I tweaked some things to make IDEA actually run well enough for me to stick to it on OS X. Short of solving the Meta key issue, here are some things I changed to make things run well... really well:
1- edit the swing.properties in the /library/java/home/lib dir and comment out the first and only line. (do this as sudo)
2- use idea with the metal lf ONLY
3- change the popup window weight from heavy to medium (known issue there). To change that you edit the idea.sh file in the idea3.0.1/bin directory.
4- turn off font aliasing in both the ide and text editor
5- use Courier New for the font, and if you change that only use monospaced fonts
6- Add: -Didea.jars.nocopy=true to the idea.sh file's start command line (last one) if you can so you don't get weird messages about jar being modified when they're really not. You will still get that error if you startup apache as a web app to debug jsps and such... filed the bug ignore it, it doesn't do anything.
7- When you're right clicking to get a contextual menu, if you choose a sub menu there, like CVS, be SURE that you're not going to hit the doc otherwise the sub menu will close immediately. If this happens, just choose the equivalent command from the regular menu or keyboard shortcut a la PC style. (meaning ctrl + xyz...)
8- edit the idea.sh file and remove the direct reference to java. you will see something like ./../jre/bin/java in the last line. remove everything except for the word java and everything after it.
If I missed something that someone else has done, please let us know. I've posted this to the Apple list.