I had a not-so-good experience with the upgrade from 6.0 to 6.1.
My car was set to power-saving "nightly" mode, and apparently when it started to do the upgrade from 23:30 as scheduled, the car turns off, even though it is mid-way through an upgrade.
When I went to drive the next time, it takes several minutes to start, center console is completely black and unusable, charge port cannot be opened, turn signals make no noise (but thankfully LEDs still work), fan and a/c unusable (caused some interesting issues with car fogging up trying to get home that night in the cold...)
Tesla service center has managed to get it fixed today remotely, after re-sending the firmware update and resetting driver and center screens a couple of times each.
A shame to find this sort of software bug, but I am glad my car is back to life. I enjoy the reversing lines on the rear camera in 6.1, really missed not having those after too many years relying on it in other cars here.