BookBeast:

What I am wondering about is whether other states will recognize same-sex marriages performed in CA. ... I don't know whether "marriage transfer" between states is mandated by federal law or what. Or, if it is, whether that federal law will by intention, phrasing or some other loophole prevent same-sex couples married in California (or Massachusetts) from having their marriage recognized elsewhere.

Bookbeast -- I have written a blog post which addresses the question you asked. Is it at:

<link>

Please feel free to take a look.