If you're tempted by all the benefits of rooting your HTC EVO 4G but are overwhelmed by the multi-step process to get it done on Android 2.2 (Froyo), then the just-released unrevoked 3.2 is what you've been waiting for.
The one-click root method keeps all of your data, permanently unlocks NAND, turns off security, maintains your PRI version, installs a custom recovery image (ClockworkMod or other), and loads up su/superuser tools. Yes, all of this in just one click.
The build was pulled a few hours after it was released due to "some strange problems" (see official message below) and is actually still unavailable as I write this, but it's expected to be back up soon. Depending on when you're reading this, it may even be available now.
Unrevoked 3.2 is said to support all Android versions on the EVO, not just the OTA 2.2, and works with Windows, Linux, and Mac.[xda-developers | unrevoked] Thanks, MsRandall & Henry!