Did you install TWRP and then take the OTA, now you can't get your phone to boot normally, but you do see TWRP?
Here's the easy fix:
If you have ADB access, plug in your phone and run this:
adb shell dd if=/dev/block/platform/msm_sdcc.1/by-name/fota of=/sdcard/fota-backup.img dd if=/dev/zero of=/dev/block/platform/msm_sdcc.1/by-name/fota
If you DONT have ADB access (because of an early build of TWRP), you can simply use TWRP's awesome "terminal command" option to run the following:
dd if=/dev/zero of=/dev/block/platform/msm_sdcc.1/by-name/fota
After that finishes, you can reboot and continue on your happy way!
Let me know if this helps anyone!
As usual, I'm on #lg-g2 in Freenode as IOMonster, if I'm around I'll be happy to help wherever I can.