I think you nailed the marketing of this change. Though, if Flickr posted the steps/goals to making the user a "priority" rather than a "product," I would be more convinced. A cursory read of their TOS doesn't indicate any changes (though this may be premature as the changes are not in effect), and their (1)non-blog upgrade post doesn't seem to indicate any changes in data collection/selling.

As an aside, if you were looking to subscribe to their Pro product, the link in the blog post contains a coupon for $15 off their yearly subscription.

1. https://www.flickr.com/lookingahead

Are we sure they still won't sell you to advertisers in addition to subscription fees?

your own cloud will cost you less and it will be much safer privacy wise until these smugs change their ToS again and throw you over deck