The object.content field (activities.list and .get) is documented as "The HTML-formatted content, suitable for display." However it only covers the content added at the time of sharing and does not include attachments.

There's an ongoing problem that new attachment types (eg Soundcloud) don't necessarily appear in the API output. For attachments that do, the object.attachments[].content only shows the plain text, not the full html as seen in the desktop Web UI.

So if you were using the API to get the G+ posts for onwards transfer into another system, the API coder needs to recreate each attachment html and gets no hints from Google on how to do this.

I've created a feature request in the issues database to deal with this. I feel that object.content really ought to be a full html rep of the whole item as seen in the desktop UI. But I guess this might break existing code (like my own!)
https://code.google.com/p/google-plus-platform/issues/detail?id=641

Thoughts?