Okay...24 hours down with the update and time for well, an update:
I am a very light PHONE user, but I was encountering the silent call issue a couple times a day. Since the update was rolled out I have NOT encountered that issue again. This includes making periodic calls to voicemail just to see if it's working. From this end, the update is fantastic. I had a couple of phone-in court hearings the other day and found myself pre-emptively rebooting the phone a few minutes before I expected them to call.
Performance otherwise has remained good. I do not run any performance benchmarking apps, so I cannot give a quantifiable measure here, and my phone was snappy before the update. The 3G speeds appear to remain much better than pre-update.
HOWEVER...I have encountered some random crashes from the browser, even when loading pages that I successfully visited prior to the update. I also encountered a system crash/lockup when the widget clock auto-launched last night before bed (this was with the charging cable plugged in, FWIW). The phone rebooted itself and the issue was not repeated.
All-in-all the update has been entirely worth it. I cannot specifically tie the minor issues that I have experienced since to the update, either.