Not disappointed at all, in fact, thoroughly happy with v9. I'm not seeing any of the regressions that others are seeing, other than for around the first 25 or so miles Autopilot was a bit unstable around corners. But it seems like after about 50 miles of driving, Autopilot is a totally new beast, able to take on crazy sharp turns, most cloverleafs, etc. Definitely next level capability for me.
Lane Change behavior is pretty awesome. If you flick your turn signal on with a car directly next to you, it seems to make a decision between whether to speed up (within TACC limitations) to merge ahead of the person or to slow down and go behind.
Overall sure, you can say it's the same set of Autopilot features, but everything just feels better now. Sure I can't wait for more automation features, but for now, v9 was more of an update than I expected. Especially compared to all the ridiculous hyping around v8 and it was basically just a basic reskin of the UI.
And I guess I'm in the minority of people who like the new UI changes.