For anyone that comes across this...
I moved from Windows 7 to OSX Mountain Lion and when running all of the pre-existing tests in OSX, I was no longer seeing the Request Body in the Raw tab. I was able to quickly get it working by doing what is described in this link:
viewtopic.php?t=5440In a nutshell, you have to go into Preferences-->Editor Settings and check "Vaidate Requests" and "Validate Responses". After doing this, I started seeing the Request Body in the Raw tab.