Editing in External Editor Has Changed
If the edit creates layers, like adding text with PS or Pixelmator, the file must be flattened before saving. Otherwise the Save To navigation window appears with the Master/Originals folder as the default location. If saved there the copy that was first created remains just that, a copy of the original and the layered file is lost to iPhoto in the Masters folder. Bottom line, flatten the image before saving if the editor presents a Save to window.
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Additional edits by the external editor do not create another copy but are applied to the first edited copy. Therefore, any edit with an external will result in the two copies being displayed in iPhoto side by side.
Previously, flattening the image and saving as a jpg would have the modified version replace the original as the displayed version. just like when edited by iPhoto. No longer true with iPhoto 11.
OT
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