I got 8.0 a couple days ago and spent some highway time with it yesterday. The differences in AP seem subtle to me, but generally a bit improved. I like the new AP display and especially the white border nag. I saw it every time and never heard an audible nag. Very nice. Lane change seems faster and more decisive. Regarding AP generally, I continue to maintain it works brilliantly when used as intended. Most of the criticisms I see here are either "first world problems" (minor things compared to the very major advance AP represents) or griping by those who don't want to pay attention or touch the steering wheel. In my experience, under the right conditions, AP is a delightful technology that has greatly improved by enjoyment and safety on the road.
I'm neutral on the full screen map display. The image is large and uncluttered, which looks nice, I guess. I found it no trouble to tap the screen to pull up the top menu.
I like the new charging graphic which shows the battery on the underside of the car. My kids thought it was cool to see where the big battery actually sits. It's a bit harder to set the charge limit precisely at 80% where I usually keep it, but this really doesn't matter.
I do not understand the new media player. I don't want to bash on it too hard because it may just be a learning curve issue and I haven't spent much time trying to puzzle through it. My first impression, however, is that it's less intuitive and less convenient, requiring more navigation inputs than before. I do not understand what problems existed previously that this update is meant to solve. As many others have noted, USB is especially inconvenient now.
New scroll wheel controls seem cool except I haven't got them figured out yet. I accidentally popped open the pano roof several times yesterday, but hey, I did that before 8.0, too.
I like seeing the text version of what the car thinks I'm saying. It was entertaining this morning to try to get it to "play Dawes," resulting variously in dog, god, and doh. However, when I said "play 'all your favorite bands' by dawes" it worked perfectly.
Generally speaking, I get excited about updates and I love the concept of a car that "gets better" over time. On the flip side, somewhat to my surprise, I do find myself annoyed by the never-ending learning curve. One of the nice things about keeping a car for a long time is that you learn all the ins and outs of its controls. Even if the user interface sucks (I'm looking at you, BMW), once you figure it out, you settle in and can "become one with the car." With the Tesla, stuff changes every few months. I'm not complaining about getting new features - it's exciting and fun! I'm just saying there's a downside to it - like at the moment I don't know how to use my media player.