I figured that I would post this to help out anyone that may have encountered a similar problem this evening. I was most glad to see that an update was available for the One X – finally 4.1 was becoming available to SIM free handsets like mine. However, after successfully updating, I realized I wasn’t getting any mobile data or 3G connection. Using search engines, I wasn’t able to find anyone else with this problem or reporting it at least.
I did however find a solution. If you go to settings, then select ‘mobile data’ (not the on/off slider) you’ll get an array of options. Then select ‘access points’, then select your network (in my case everything everywhere). Boom, 3G connection restored!