Embed Metadata for PDF consistently adds 0.5MB to book size
I have noticed that the much awaited Embed Metadata button for PDF's (thank you, Kovid!) quite consistently (though not always) adds 0.5MB to book size, way more than would have been expected (a 1.1MB book becomes a 1.6MB book, for example).
Interestingly, this 0.5MB can be then made disappear by resaving the pdf with Adobe Acrobat Professional, for example.
Not sure what's going on, but it does seem like a bug and not a design feature, though I am not sure exactly what is being embedded or how.