Just a heads up, if you're using Straight Talk's BYOP sim card and your data quit working, you may have been transitioned to new apn settings. I read about it here http://forum.xda-developers.com/show....php?t=2310215 in the Nexus 4 forums.
It seems users there lost all mobile data connectivity after their service renewed. The new apn settings seemed to have restored their data connectivity. I suggest making a second apn setting on your phone with the new settings I've posted below. The reason why I suggest a second apn is so you can easily switch between apns if you lose data connectivity on the new apn, I see it as an easy troubleshooting step down the road.
Here is the new apn
Name: Straight Talk
MMS Proxy: mms3.tracfone.com
MMS Port: 80
Straight Talk now let's you type in your phone number on their website to look up which apn settings you should be using, it can be found here
I hope somebody finds this useful and hopefully doesn't cause confusion.