I have had a Rogers HTC One X for just over a week. I'm coming from a Galaxy Nexus (and GS2 before that).
I really like the hardware, it just feels so good in hand. I don't like the power button at the top. I use my phone one handed and I get the sense (haha) that it's going to slip out of my hand every time I turn it on. I do have a workaround though... I now hold it angled downward when I wake it from sleep - with the top of the phone resting on my fingers - so the phone moves up rather than down when I power it on. I hate the bottom row of arrow keys, I would prefer the stock ICS keyboard but since it's not on the phone I happily use SwiftKey.
The phone is FAST, no slowdowns whatsoever. It is so fast, it has made me notice hiccups on my Galaxy Nexus. When in LTE coverage, I'm getting 25-50Mbps download speeds. Battery will last me 2 days of light to moderate usage (just over 3hrs of screen time).
Sense 4 isn't terrible - I like it better that TouchWiz - but I'll take STOCK Android any day of the week. That said, Sense silliness is my biggest complaint about the phone.
I take a lot of pictures with my mobile phones - and the camera on the One X is great - but HTC makes you click more than you have to in order to do something as repetitive as SHARING A PICTURE.
When you are viewing a photo and click on "Share", you are immediately given some default choices. As far as I have been able to determine, these cannot be changed (see attached share.png). These are completely useless. Who shares via Bluetooth? Am I really going to start sharing on Sky Drive because it's right there? In order to get to the apps I want, I need to click on "See all". The apps under "See all" default to alphabetical order but they will rearrange themselves based on use - but they will NOT show up in the first menu.
Maybe it's not that big a deal and I'm just upset at the arrogance of HTC for trying to push their preferred services on it's users. But I think not. It's a usability blunder that adds steps to my workflow for no justifiable reason. At least you can "disable" apps - like I did with "Facebook for HTC Sense" and "Twitter for HTC Sense" which will remove them from the menu, but I shouldn't have to remove bluetooth. Even if I did, my preferred apps still wouldn't show up first. Don't even get me started on multiple photo selection...
Hopefully Paul can work his magic and come up with a solution :-)
Other than that, I love the phone.