I've been looking at and watching this little wren for three years now. I am pretty close to certain it is a Bewick's wren, which is supposed to be rare / endangered east of the Mississippi.

From the photos I'm seeing on the Cornell site and the American Bird Conservancy's Field Guide, it looks like a Bewick's, not a Carolina, which are plentiful in this area.

How rare is the Bewick in my area, really? We do have the perfect habitat for the Bewick and Carolina.