Colan Nielsen shared a new feature he spotted in the Google My Business dashboard. Under the products tab (not everyone will see this), Google is providing "suggested categories" for you to add based on how Google understands your business.
Colan shared a screen shot of this in the Local Search Forums:
He said "Google is offering these pre-selected categories" and he is about to release some research around if using the products section helps or not with local SEO, so he said things should become more interesting.
Forum discussion at Local Search Forums.