Installed the update early this morning (eastern time) and used it for my commute which is a mix of surface streets and interstate. I'm impressed overall, but did have to take over steering a couple times, notably when the car seemed to pull towards a highway exit lane opening and I wanted to continue straight. One other situation involved a curved surface road with an intersecting road in one of the curves. The car seemed to quickly lose track of the road but did not display any warnings instructing me to take over.
Highway driving was exceptionally smooth. After a couple minutes auto steer had gained my trust and it did a brilliant job, even when my car was pointed into the sun. The car does seem to react a little slower to steering than I typically do; in other words I'll bank into a turn just before a the road starts to bend, autopilot waited until the lanes actually curved. That was a little unnerving at first as I was wondering "should I grab the wheel" but after a few miles I was satisfied it would handle correctly. Auto lane change was particularly impressive, although there wasn't any traffic in the next Lane when I tried it. One thing to keep in mind is that you need to fully engage the turn signal stalk (not just tap it like you'd normally do when signaling a lane change) then manually turn it off when you're finished merging.
Performance on surface streets was remarkably good, and yes, I'm aware it's designed for highway use. The roads in my area are generally well maintained and marked, and the steering / TACC made for a smooth experience, very similar to what I'd expect from a human driver. One word of caution, when stopped at a traffic light with auto steer engaged the car ahead of me turned right on red and my car started to lurch forward, which would have taken me through an intersection with a red light. In the past, with TACC enabled I'd get a "hold" notification when stopped for more than a brief time and have to tap the accelerator pedal to continue. That behavior seems to be changed in this release.
For what it's worth I didn't have any nag warnings to put my hand on the wheel, although since this was all new to me I didn't go extended periods without grabbing it instinctively.
The auto steer / TACC display on the instrument cluster is familiar and intuitive. At first I didn't like the toy car from the leaked V7 screen shots, but after driving with it I'm happy to say it makes total sense to display things this way. It's a good presentation of information related to auto pilot, although I'm not sure how useful it would be in pre-autopilot vehicles. The regen app is similarly simple and familiar, albeit smaller and in a different location. The apps on the 17" display operate the same way as in V6 but have squared edges
Overall, I'm happy with this release. I'd be a little hesitant to say it was "worth the wait" since it has been a year since it was announced, but it feels refined, well engineered and very much suited for the Model S.