Rich snippet rating stars
1) I've seen a few sites use the start ratings rich snippet to review themselves rather than third party products which it was intended for. E.g. a website owner might publish their testimonials and each testimonial will have a 5 star rating as well. Webmaster would aggregate these and display it on their site. Is this allowed?
2) rich snippet for organic listings are pretty straight forward, just have the correct markup and google will choose to use these on the results depending on their own criteria (it is asumed this is down to trust, authority and relevancy to end user).
Does the same rule apply to Adwords or is there some other procedure required to get rich snippets published for paid search campaigns?
Re: Rich snippet rating stars
Thanks for posting in the AdWords Community!
Your questions regarding Rich Snippets in the first question would actually be better suited for the Google Webmaster Help Forum, as this topic is generally more related to Organic Search, which is completely separate from Paid Search (AdWords), so I would highly recommend you make a posting there!
I hope this helps!