Trying to root Motorola Xoom. Stuck rebooting
Ok, so it turns out that you need a different boot.img file for the Motorola Xoom wifi only model than for the 3g model. 

Click here for instructions if you have a 3g model

click here for instructions if you have the wifi only model (Including how to fix it if you've already tried using the wrong boot.img and you are being stared at by a non-responsive boot screen that has the Moto logo and the words 'Dual Core Technology')