So there's no need to urgent go around deleting things.
In any case, no tagged image should be deleted until we have deleted the ~36,000 images that have no tags on them, and about which we have precisely zero information.
If we start deleting images because people do the *right* thing by correctly citing their sources and providing information, then we'll be setting entirely the wrong precedent.
There are no legal problems with what we're doing
For now, let us just say that there are two schools of thought on that matter, as it relies on the interpretation of the meaning of "seperate and independent" in the section on aggregation. A matter for wikilegal-l, of course (and thusly cc'd).
-Martin