I'm having the same issue after the latest software update (performed on 10/25). Verizon support wants me to do a factory reset. Can't be just us...

 

I've found that it is usually a good idea to do a factory reset after a major firmware update. Yep, its a PITA to reload everything, but the performance of the device afterwards is usually worth the trouble.

 

Before embarking on a Factory data Reset, I would recommend that you first try wiping the cache partition as detailed in #1.2 of the Update Problems - Dummies Guide

 

A factory data reset didn't help me. I ended up using Odin 3.09 to flash back to the previous OS version.

 

It's the Knox apps that causes the reboots. Two things to do about it and you need to be rooted for either.
1) download Xposed Installer and install Samsung Kitkat SystemServer Crash Fix module. This will stop the crash when it happens and it won't reboot.
2) Use Titanium Backup or similar app and uninstall the seven Knox apk and the com.sec.enterprise.knox.......

 

No Root phone

Wiped cache: No Joy
Verizon said to go to BestBuy Samsung Experience have them reflash: No Joy
Odin 3 back to VRUFNC5 No Wipe: OS crashed
Odin 3 back to VRUFNC5 - Wipe: All good
Install VRUFNC6 over the air: All good (except for the normal update pains)

I did not try a factory reset since some reported that did not work. The reboots are gone and the normal update problems are being dealt with. I used Helium (carbon) backup /restore which worked well except setting up my POP3 accounts. All back to working.

 

After the update, my phone has turned off spontaneously twice. Today, it shut down and when I rebooted, the battery was at 1%. It was not hot. Android System consumed 76% of the battery.

Despite trying multiple times, I was unable to get into the Recover Mode to wipe the cache partition.

Verizon S4, unrooted.