I hear Google Product Search will be changing to "Google Shopping" and I want to know if users will be able to upload links to be displayed even if you don't have accommodating product "data" to accommodate and/or without partaking in an AdSense style pay per click model. I read a lot already but I am wondering if there is any information I missed before I throw in the towel and accept that the conclusion that it will be a completely paid service.
I think this blog post on the Google Commerce blog sums it up:
First, we are starting to transition Google Product Search in the U.S. to a purely commercial model built on Product Listing Ads.
So in essence, you will have to pay for a listing on Google Shopping. At this stage it only applies to the US site, but barring mishap it will no doubt be rolled out everywhere eventually.
If you are not marketing to the US, you can still submit to Google's Merchant Center for free.