Somehow managed to sneak in a game against the Medium AI. PvP.
He wasn't that much harder than Very Easy. I did a very sloppy 4 gate push. His first timing attacking only had about 3 units when I had about 8. Then when I pushed out, with about 10-12 units, he only had about 3-5. He actually didn't have anything Tier 2 when I ended up killing him.
There's also sorts of different little interface improvements in-game. Info boxes are slightly different. Chrono Boost had a new icon. Idle Warp Gate had a new icon. A couple sounds are different. Judicator Aldaris sounded a bit different, like they added a new filter onto his voice. Little more echo but not as loud. Also, it might have been my imagination or just a change in settings, because it seemed like my framerate was higher than usual, even though it didn't seem like I lost anything visually.
What raised my eyebrows the most was a new dialog box that popped up whenever the AI said "gg". It said "Your opponent has offered to surrender", with options to accept the surrender or not. I'm not entirely sure why that's there, but it's there.
So overall, they did add in some extra polish to the game while the beta was down. This patch is definitely as significant, if not more so, then Patch 9.