Good news, everyone!
With the latest IntelliJ IDEA 13 EAP build the IDE is almost compatible with Java 7 on Retina devices. That means you can safely switch from Apple JDK 1.6 to Oracle JDK 1.7 on your Macs. The latest build of JDK 7 (1.7.0_40) has many fixes for Retina devices, better fonts rendering, AWT subsystem and more. To switch to Oracle JDK 7 on Mac you need to download and install the latest JDK After that you need to edit /Applications/IntelliJ IDEA XXX.app/Contents/Info.plist file. Then change JVMVersion from 1.6* to 1.7*
The detailed instruction how to run IntelliJ IDEA under JRE 7 on different platforms can be found here. Window version of IntelliJ IDEA is already bundled with JRE 1.7.0_40.
Download and play with the latest EAP 132.235