I came across this during tonight's dist-upgrade:
serious bugs of proj-data (4.8.0-2 -> 4.8.0-4) <Outstanding>
#747862 - proj-data: Pakcage contains architecture dependant files in /usr/share
Summary:
proj-data(1 bug)
So I put on hold temporarily. I don't know much about the package, but, when it says it "contains architecture dependent files", I'll wait till the bugs are fixed.