Hello there. I also attempted the 4.4.2 OTA from stock 4.3, and now I'm having this exact
same issue. The device had TWRP recovery installed, so I re-installed the stock recovery. It was also rooted and a few system files were edited (lock sounds, hosts file), I reverted all the changes, did a full unroot via SuperSU and proceeded with the OTA. It seemed successful until it tried to boot.. it now freezes on the AT&T logo, as the OP mentioned. I installed TWRP recovery again via Odin so I could back up all the data from the phone and do a factory reset. Unfortunately, this did not fix the freezing.
I've attempted reverting back to the latest official Odin .tar (4.1.1), which I've now learned is not possible since the 4.3 update and its locked bootloader. It would seem that the only thing that would do the trick now would be an Odin-flashable 4.4.2 tar. For now, I've installed CyanogenMod as a temporary solution.