Upgraded WP and Lost Header Image using Twenty Ten theme

Did you edit the theme at all?

No edits

Would a complete delete/uninstall and reinstall clear things up?

No.

Check your uploads path in Settings->Media. It should be blank in most installs but can sometimes become populated incorrectly during an upgrade

It was blank. However to be sure I populated the entire URL. either way, no affect.

Shut off a bunch of widgets, image came back.
Thanks