The fixed zoom bug reported here
is still present.
Something similar happens also here:
1) Menu -> Settings -> Advanced -> Auto zoom: No auto zoom
2) Go back to map and set the zoom to the level you want. E.g. set it to maximum to see the difference well.
3) Menu -> Reports -> Open any report you want to see it on map. Then the map moves to the traffic report location and changes the zoom - OK.
4) Close the pop-up via the Close button. In the case described in the URL above the zoom returns back and is forgotten on the next application start. But after the steps described here it's gone already now.
Sometimes the zoom changes also when the navigation is started.
SGS2, stock ROM 2.3.5
P.S.: I hope you won't overlook also the bug reported here
today. This is difficult to repeat with the new client as there are no roads around not recorded in the map yet but I guess that the new version still has also this bug.