The ever-thoughtful and eruidite Volokh Conspirtators have a running thread of FISA commentary.

Here is the most recent article. You can scroll down to the bottom of the post for links to the rest of the series.

The conculsion, as I read it, is that FISA is not overriden by AUMF and that any Article II argument would lose at SCOTUS 8-1, with only Thomas supporting the President. Of course, they also point out the unliklihood of this making it to the Supreme Court because no one with standing to sue is likely to know that they have standing.