The biggest virtue of property_tree is easy to use interface. If we try to make generic tree of it, it will be compromised. This should not happen, because people will then prefer to use Expat or MSXML instead.
Could you clarify (with details) how is it easier then alternatives?
I assume that by alternatives you mean above mentioned Expat and MSXML? First, property_tree supports more formats, not just XML. Second, it presents unified interface to access data regardless of format. Third, to get a value from XML file (or any other supported format) you literally need _three_ lines of code (not counting one #include). That would be much more is case of any alternative I know of. Fourth, you do not have to link to over 1 MB DLL (in case of MSXML), just to read from you XML config file that startup GUI window position is (200, 200). I believe this is enough to consider the library as having some viable uses? Best regards, Marcin