Actually, I just got my 970 about 2 months ago and was told that they ship with the stock firmware (no updates). I ran it the way it came for a month, then upgraded.
I am interested in upgrading from Linux, which has been promised (there's no mention of Mac). Although I was able to run the install program in Linux using the Wine emulator, I did so without actually connecting the serial cable afraid that I might end up with a brick. I ran the actual upgrade using my kids' Windoze box.