Linda, You are so very correct. Everything you described is what had drawn me to your site earlier this year. I was wanting to know answers to why I noticed certain business get bumped up after the photos while others did not. Clearly I knew I was missing something and naturally I want the best for my customers.
I knew I was on the right track once I heard the various strategies that Linda and her pros promote here (there's plenty of misleading info out there) because when +Local started to form, us photogs were right in the middle of all of those technical issues and needed quick answers from Google. We have info but there's plenty that we didn't know and still don't because the bigger picture for +Local is still being rolled out and of course things change so rapidly.
I am willing to share what I've seen and done... but in no way can I claim that it officially relates to ranking factors. Does it help reach a more targeted audience? Yes we have some data on that. But, what ever we uncover or share here on the forums has to be on a case by case basis only for now and is not meant to be the same for every business. Sorry for the bit of a disclaimer but I thought I'd put that out there just in case.
Do the photos and tours build trust with targeted audiences, Yes they do. Would a customer be more likely to decide to go somewhere once they knew what it offered, what it looked like, once it set those expectations? It's attractive but that's for the customer to decide.
But does it also mean that Google now knows that you are who you say you are? Yes it does, and IMO that is huge! It's now easier to detect the real from the spammy. I say, Algo, do your spam detection elsewhere!
Can't wait till we all start digging deeper on this feature.. this should be very exciting.