It has taken me some time to actually get to posting this question/comment.
I updated my Galaxy SIII to Android 4.3 when I was prompted by Verizon that it was an important update. In most cases it has been a good move. However, the update rendered my 16 gb SDHC card useless. I lost a great deal of documents, music, video and photos. This was both infuriating and saddening, since I lost some family video I had taken only the day before. I can replace some of the other data, except the card now reads as damaged whether I try to mount it in my phone or on one of my computers. Will Verizon replace the card? It was not cheap and the damage was caused by a Verizon-prompted update that was later apparently pulled back from release.
Good luck with that. I've been getting the run around from Verizon regarding the 4.3 update. Called multiple times, got transferred to Samsung (and got nowhere), and live chatted a couple times. Every person I spoke to acted like they had not heard a thing about the bad 4.3 update.