AT&T HTC One X Question from an Android Virgin

Ok so I've been a die-hard iPhone user since day one and have never felt the need to switch over to Android until now. I'm eyeing the HTC One X on AT&T and have a question for you Android guys. How easy would it be to install 4.1 Jelly Bean on the One X once Google releases it? The whole rooting and ROM stuff is new to me since I've never really done it on the iPhone (other than jailbreaking). Is ROM installation simple? And is the HTC One X a good phone to install clean versions of Android or custom ROMs? Any answers or advice would be greatly appreciated. I'm looking forward to diving into the Android environment and just want to make sure that I buy the best AT&T device that gives me the most control and flexibility to customize.