Well, BD, it certainly is wrong for Barry to be calling himself a Muslim because, well, it's patently false.
While Barry was exposed to Islam as a youngster and went to muzzie schools at that age, his in-your-face socialism pretty much negates any kind of religion and religious influence by that social/political/religious system, or other religion.
Barry uses religion in whatever form as a matter of convenience and as a smokescreen. He tries to portray himself as a devout Christian and utterly fails, largely because he attended Wright's church to be seen there -- not because he's devout.
In short, Barry himself is a walking, talking, breathing lie. But his slip of the tongue isn't really noteworthy, regardless what the AP does, because he's no more a muzzie than I am.
Barry worships himself and no other.