I received the Oreo update on Saturday and have had major issues with 2018 Camry's Entune audio system since then. While my phone does connect via Bluetooth, the car's voice recognition system can no longer find any contacts in the phone book even though they all show on the display screen. This was not the case prior to the Oreo update. Voice recognition consistently found almost any name that I asked to an initiated the call. The other issue, somewhat less important, is that steaming apps like Pandora, IHeart, etc. will now connect and disconnect constantly and even when connected, the music does not play through the car's speakers, only through the phone's. On the major Toyota users website someone with similar problems in his Camry had no problems in his Jeep. It's hard to know whether this is a Samsung, Android, Verizon or Toyota issue with Oreo but hopefully someone will solve it.
The other problem is decreased battery life. It appears that some apps even when inactive are still drawing battery power. I will get a notice that X number of apps are still using power. This is backwards step from Android 7.
Some corrections to my original post. The Camry's voice recognition system is now working normally with my Galaxy S8. It's finding and bringing up my contacts for dialing or for sending text messages. It must have been a temporary glitch. That leaves the issue with Entune's streaming apps and the decreased battery life. I estimate that to be 10-15% less time than it was with Android 7.