I agree with you, Michael.
I think that it is possible to get synths to outrank panos, but you'll have to go all out with the synth's metadata (description, tags, geotag, highlights, etc.) in order to make that happen.
I'm not sure how it would play out if you had a synth and a pano that had identical metadata, though.
The closest that I've seen to anyone on the team mentioning what factors play into ranking up a synth or pano was here: http://photosynth.net/discussion.aspx?cat=a6bad539-de7d-4a16-8c4d-b143f7d5f984&dis=768ddd23-9805-4fe4-b478-d525c8f3197a (although that was purely about synths).