I did the OTA update to Kit Kat yesterday evening. The only issue I had was the connection to my Wi-Fi range extender. My phone said it was connected to it, but launching any app that required an internet connection failed. I could connect to my main router and it worked fine. This lasted about an hour, then the connection to the range extender worked fine and has since. I'm also not getting the typical unstable Wi-Fi messages anymore. It appears Verizon has fixed the Wi-Fi issue. So far everything seems to work fine.