How does Bridgeman vs Corel Art. Library (or a comparable case) holds up in this discussion?
There are two problems:
1) Bridgeman vs Corel applies in the USA only, as you pointed out. In a large number of countries it is difficult to know whether a photograph will be considered to be a reproduction, and to yield copyright or not. The USA are a favourable exception in this respect. Some countries will make a distinction between photographs and "mere reproduction by technical means", the former yielding copyright but not the later.
2) In lots of cases, it is difficult to know whether the original work in copyrighted or not. This is the case of works by unspecified authors ("unspecified", not "anonymous"), or works by people whose date of death is unknown. There are cases in which uncertainty as to these results in a de facto lengtening of the copyright. For instance, a semi-famous French photographer is not in the public domain, but before his death, an edition company was founded, which has published photographs under his name since; hence it is clear that the most recent photographs cannot possibly be in the public domain; but also all works published under this photographer's name in his later years are suspicious and unusable. I would go as far as to suspect that some people make information deliberately difficult to find for this reason.
-- Rama