So far, these are the things I've gotten to work well on my Pi 4...
Amazon prime video
Slack through the web interface
Discord through the web interface
Wolfenstein Enemy Territory Legacy
Intellij Community Edition (Primarily doing Kotlin development)
Dungeon Crawl Stone Soup (Tiles Version) (super important
These are all capabilities that I never got running on my PI3, (or that the performance was degraded enough as to not be worth it).
In particular Inteliij wouldn't even load on a pi3. And while it is a little slow on the pi4, it works and is stable and is usable
I'm super excited about the accelerated 3d. I've been testing out as much as I can with that, and so far I've been very impressed. It's a far cry from the stability the old experimental drivers exhibited.
Thanks for all the hard work.
My daughter and I are both using the pi4 as our main computing platform, and so far I'm pretty happy with it