On 4 January 2015 at 19:54, Peter Dimov wrote:

I notice that the library list at the website has a "First Release"entry for each library; these apparently come from the tag <boost-version> in libraries.xml, which also has an <update-version>. The meta/libraries.json files, however, appear to have no such data. Is this intentional?

Yes, the update scripts manage version info. They didn't at first which is why some of the older metadata files have it.