There are no settings in Aperture -> Preferences -> Photo Stream regarding which image to upload. In fact, I couldn't locate any preference setting anywhere in Aperture that would give a user the choice to upload the original versus the edited version of the file.
This looks like a bug to me unless I'm really missing something.
Eric, your Aperture acts differenty from mine. What is your Aperture version? Have you upgraded to 9.4.3?
When I share to the Photo Stream, Aperture will upload the current version; the original will be uploaded directly after import, if the stream is set to "Automatic Upload".
Infact, I can add as many new versions to the stream as I want. Only I have to share again after each edit.
Three versions of the same image in My Photo Stream.
I am running the same version as you but I want to clarify, I'm talking about Shared Photo Streams (ie the private stream you create and invite friends to view) not my personal Photo Stream. I haven't watched the behavior of my Photo Stream but as you said, since it's set to automatically upload, it will upload the originals.
The problem I have is when I create a Shared Photo Stream, it uploads the originals, not the edited files and there doesn't appear to be anyplace where that's set. In iPhoto, it always uploads the edited versions.