Just updated to ARHD 10.2 Jelly Bean and boy it rocks!
I love my One X but I love it even more now with Jelly Bean. Albeit this is a stable release, it works well, it's fast, smooth and hardly any lags.
The new keyboard is a joy to use with the wider keys and removal of the arrows. Prediction is pretty good as well.
Homescreen now loops which is useful. Shades of blue all over the place apart from status bar but there's a blue mod available already on XDA.
Google Now is fan-bloody-tastic! It just works great, ask the weather it tells you, ask if it will rain on Monday it tells you, ask to convert £10 into Indian rupees it tells you, ask to calculate something it does it for you, best one yet, say your in the middle of nowhere, ask it for the nearest pub and it'll tell you and load up directions for you. Very useful if your in a random area and look for a drink! Quite nifty and sure will get better over time.
It feels like a new phone! I love it.