Firmware update 4.70 has been released, no change log, Garmin???

These are released in a phsed roll-out. The change logs are not posted until we hit 100% rollout.

Not a good solution. The user should see it to decide, if it is worth to install the update…

I agree. This behavior does nothing to benefit their customers. 

The user can see what the update includes if they click view details before installing the update in Garmin Express. 

I got offered the update in Garmin Express, but no release notes where shown.

IMO it would be good practice to post release notes here at the start of roll out and make clear it's a phased roll out. Better more communication than less...

Garmin-Leslie, what is the reasoning that leads Garmin to conceal the changes in an update between the time the update is announced and the rollout is complete?  The reasoning is not obvious to me.