From the front page article...
The update also includes the following improvements:
- Adds over 300 new Emoji characters
- Adds Spotlight suggestions to Look up
- Prevents Safari from saving website favicon URLs used in Private Browsing
- Improves stability and security in Safari
- Improves WiFi performance and connectivity in various usage scenarios
- Improves compatibility with captive Wi-Fi network environments
- Fixes an issue that may cause Bluetooth devices to disconnect
- Improves screen sharing reliability
Granted, that is not a complete list of all the improvements. However, it does show that some work was done on Safari.
Even though it is early on, I haven't run into any Safari loading problems, yet. I did have the incomplete loading of some pages before the updates.