Southeast US: mystery spider

[pipisafoat]

I have been meaning to get a picture of this spider for identification purposes (I think it's an orb weaver? Any thoughts on that definitely welcome!), and I sort of got distracted while I was out there.

All these pictures can be clicked for larger/uncropped, but those are pretty huge, so click at your own bandwidth's risk.

( 3 different angles of the same spider )