Just got a software update to version 5.10 through Garmin Express. No mention yet on the Forum or elsewhere, so the usual (...) question:
What or where are the Changenotes?
I think that's correct. As far as I know there is no archive of software changes other than the information on this forum. Garmin personnel used to announce the new software availability and changes to the software, but that seems to have stopped.
FWIW, I checked the 1030, 830, and 530 forums. The 1030 software went from version 9.00 to 9.10 about 30 days ago. The 830 and 530 software was upgrade from 5.00 to 5.10 about 30 days ago. The changes were similar to the changes in the Explore 5.10 software.